Thursday, February 11, 2016

Brhadaranyaka Upanishad 1.4.9 & 1.410; Brahmakandika Aham brahmasmi and Shankara Bhashya

Verse 1.4.9:
तदाहुः, यत् ‘ब्रह्मविद्यया सर्वम् भविष्यन्तः मनुष्या मन्यन्ते, किमु तद्ब्रह्मावेद्यस्मात्तत्सर्वमभवदिति ॥ ९ ॥
tadāhuḥ, yat ‘brahmavidyayā sarvam bhaviṣyantaḥ manuṣyā manyante, kimu tadbrahmāvedyasmāttatsarvamabhavaditi || 9 ||
9. They, say: Men think, Through the knowledge of Brahman we shall become all.[22] Well, what did that Brahman know by which It became all?
In the words, ‘The Self alone is to be meditated upon’ (I. iv. 7), the knowledge of Brahman which it is the aim of the whole Upaniṣad to impart, has been briefly indicated. With a view to explaining this aphorism, the Śruti, in order to state the necessity of this knowledge, makes this introduction: They say. ‘Tat’ (that) is preparatory to what is going to be unfolded in the next clause. ‘They’ refers to- those seekers of Brahman who, on getting a teacher who is like a boat on that boundless ocean which has for its water the painful struggle due to rotation in the cycle of birth, decay and death, desire to cross that ocean, and being disgusted.with thejworld of means and ends consisting [Page 144] or righteousness and unrighteousness, their means and their results, long to attain the eternal, supreme good which is entirely different from the above. What do they say? This is being stated: Men think,‘Through the knowledge of Brahman or the Supreme Self we shall become all, excluding nothing.’ The use of the word ‘men’ indicates their special aptitude for this as they are specially qualified for the achievement of prosperity and liberation, This is the idea. As those seekers think with regard to rites that they would bring sure results, similarly they think that the knowledge of Brahman is sure to lead to identity with all, for the Vedas are equally the authority for both. Now this seems to be something inconsistent, hence we ask, what did that Brahman by knowing which men think they will become all,know by which It became all? And the Śrutis say that It is all. If It became all without knowing anything, let it be the same with others too, what is the use of the knowledge of Brahman? If, on the other hand, It became all by knowing something, then this identity with all which is the result of the knowledge of Brahman, being the product of knowledge, becomes just like the resuít of an action, and therefore transitory. There would also be a regressus in infinitum, viz. that too had become all by knowing something else, that earlier thing, again, by knowing something else, and so on. We take it for granted that It did not become all without knowing something, for that would be distorting the meaning of the scriptures. But the charge of the result being transitory stands, does it not?—No, none of those charges can be levelled at it, for there is a particular meaning to it.
[Page 145] If indeed that Brahman became(?) all by knowing something, we ask, what was it? T(?) is objection the text gives the following absolutely flawless(?) reply:


An assembly of Brahmanas - seekers of Brahman - got together. They had a doubt or a question "Some men manuṣyā manyante say that by brahmaviyda we can become everything; brahmavidyayā sarvam bhaviṣyantaḥ We see Brahman is everything. So if Brahman is everything then how does Brahman become everything - with or without knowledge. Then the look for problems with this.
If Brahman became everything without gaining knowledge then why cannot we become everything without gaining knowledge
If Brahman became everything by knowledge - of something else - like we become everything by knowledge of brahman - then the problem that something else will have to know something else to become everything.. and this will lead to infinite regress
If Brahman becomes everything by knowing itself - the problem is subject and object become one and the same and it is illogical - subject and object are ever different.

If it becomes anything it will become impermanent.
So question is How did brahman become everything.
tadbrahmāvedyasmāttatsarvamabhavaditi 


Next sloka is Brahma-kandika -  a very very famous and important mantra.This is because it contains the most famous mahavakya aham brahmasmi.


Verse 1.4.10:
ब्रह्म वा इदमग्र आसीत्, तदात्मानमेवावेत्, अहम् ब्रह्मास्मीति । तस्मात्तत्सर्वमभवत्; तद्यो यो देवानाम् प्रत्यबुभ्यत स एव तदभवत्, तथार्षीणाम्, तथा मनुष्याणाम्; तद्धैतत्पश्यन्नृषिर्वामदेवः प्रतिपेदे, अहम् मनुरभवं सूर्यश्चेति । तदिदमप्येतर्हि य एवं वेद, अहम् ब्रह्मास्मीति, स इदं सर्वम् भवति, तस्य ह न देवाश्चनाभूत्या ईशते, आत्मा ह्येषां स भवति; अथ योऽन्यां देवतामुपास्ते, अन्योऽसावन्योऽहमस्मीति, न स वेद, यथा पशुरेवम् स देवानाम् । यथा ह वै बहवः पशवो मनुष्यम् भुञ्ज्युः, एवमेकैकः पुरुषो देवान् भुनक्ति; एकस्मिन्नेव पशावादीयमानेऽप्रियम् भवति, किंउ बहुषु? तस्मादेषाम् तन्न प्रियम् यदेतन्मनुष्याविद्युः ॥ १० ॥
brahma vā idamagra āsīt, tadātmānamevāvet, aham brahmāsmīti | tasmāttatsarvamabhavat; tadyo yo devānām pratyabubhyata sa eva tadabhavat, tathārṣīṇām, tathā manuṣyāṇām; taddhaitatpaśyannṛṣirvāmadevaḥ pratipede, aham manurabhavaṃ sūryaśceti | tadidamapyetarhi ya evaṃ veda, aham brahmāsmīti, sa idaṃ sarvam bhavati, tasya ha na devāścanābhūtyā īśate, ātmā hyeṣāṃ sa bhavati; atha yo'nyāṃ devatāmupāste, anyo'sāvanyo'hamasmīti, na sa veda, yathā paśurevam sa devānām | yathā ha vai bahavaḥ paśavo manuṣyam bhuñjyuḥ, evamekaikaḥ puruṣo devān bhunakti; ekasminneva paśāvādīyamāne'priyam bhavati, kiṃu bahuṣu? tasmādeṣām tanna priyam yadetanmanuṣyāvidyuḥ || 10 ||
10. This (self) was indeed brahman in the beginning. It knew only I(?) as. ‘I am Brahmaṇ.’ Therefore It became all. And whoever among the gods knew It all became That; and the same with sages and so on. The sage Vāmadeva, while realising this self) as That, knew, ‘I was Manu, and the s(?)’ And to this day whoever in like manner knows It as, ‘I am Brahman,’ becomes all this (?)verse). Even the gods cannot prevail against him, for he becomes their self. While who worships another god thinking, ‘He is one, and I am another,’ does not know. He is like an animal to the gods As many animals serve a man, so does each man serve the gods. Even if one animal is t(?)n away, it causes anguish, what should one; (?) of many animals? Therefore it is not liked by them that men should know this.
Prima facie view: Brahman here must be the conditioned Brahman,[23] for then only can the identity with all be t(?)roduct of effort. The Supreme Brahman cannot (?)me all as a result of knowledge. But this identity (?) all is spoken of as a result of knowledge: ‘There (?) It became all.’ Hence the Brahman referred to i(?) passage, ‘This was indeed Brahman in the beginn(?) must be the conditioned Brahman.
Or, since(?)n alone are qualified (for this identification with(?)the word ‘Brahman’ may refer to a future knowe(?) Brahman who will be identified with It. For in (?) passage, ‘Men think... we shall become all’ ((?). 9), men have been introduced, and it has alread(?)en said that they alone are specially qualified for (?) practice of the means of prosperity and liberatio(?)neither the Supreme Brahman nor Hiraṇyagarbha(?)he conditioned Brahman. Therefore by the word (?)ahman’ is meant a man who through the knowledge(?) the conditioned Brahman—identified with the who(?)niverse—combined with rites, attained identity with(?)e conditioned Brahman (Hiraṇyagarbha), and (?)ing away from all enjoyments (in that ! [Page 147] state) and having broken his ties of desire and action by attaining everything, sought unity with the Supreme Brahman through the knowledge of It. It is a common occurrence in the world that words are used having reference to future states, as in the sentence, ‘They are cooking rice,’[24] and in the scriptures too, ‘The monk,[25] after performing a sacrifice in which wishing fearlessness to all beings is his fee to the priests,’ etc. (Va. X.). Similarly here also Brahman means a man desiring to know Brahman and aspiring identity with It. This is the view of some.[26]
Reply: Not so, for that kind of identity with all would be open to the charge of transitoriness. There is no such thing in the world that really assumes a different state through some cause and still is eternal. Similarly, if identity with all be due to the knowledge of Brahman, it cannot at the same time be eternal. And if it be transitory, it would be, as we have already said, like the result of an action. But if by identity with all you mean the cessation, through the knowledge of Brahman, of that idea of not being all which is due to ignorance, then it would be futile to understand by the term ‘Brahman’ a man who will be Brahman. Even before knowing Brahman, everybody, being Brahman, is really always identical with all, but ignorance superimposes on him the idea that he is not Brahman and not all, as a mother-of-pearl is mistaken for silver, or as the sky is imagined to be concave, or [Page 148] blue, or the like. Similarly, if you think that here also the idea of not being Brahman and not being all that has been superimposed on Brahman by ignorance, is removed by the knowledge of Brahman, then, since the Vedas speak the truth, it is proper to say that what was really the Supreme Brahman is referred to in the sentence, ‘This was indeed Brahman in the beginning,’ for that is the primary meaning of the word ‘Brahman.’ But one must not think that the word 'Brahman' here means a man who will be Brahman, which would be contrary to the meaning of that term. For it is wrong to give up the plain meaning of a word used in the Śruti and put a new meaning in its place, unless there is a higher purpose behind it.
Objection: But the fact of not being Brahman and not being all exists apart from the creation of ignorance.
Reply: No, for then it cannot be removed by the knowledge of Brahman. This knowledge has never been observed either directly to remove some characteristic of a thing or to create one. But everywhere it is seen to remove ignorance. Similarly here also let the idea of not being Brahman and not being all that is due to ignorance, be removed by the knowledge of Brahman, but it can neither create nor put a stop to a real entity. Hence it is entirely futile to give up the plain meaning of a word used in the Śruti and put a new meaning in its place.
Objection: But is not ignorance out of place in Brahman?
Reply: [Page 149] Not so, for knowledge regarding Brahman has been enjoined. When there has been no superimposition of silver on a motheṛ-of-pearl, and it is directly visible, no one takes the trouble to say it is a mother-of-pearl, and not silver. Similarly, were there no superimposition of ignorance on Brahman, the knowledge of unity regarding Brahman would not be enjoined in such terms as the following: All this is Existence, All this is Brahman,[27] ‘All this is the Self' (Ch. VII. xxv. 2), and This duality has no existence apart from Brahman.[28]
Objection: We do not say that there is no superimposition on Brahman of attributes not belonging to It, as in the case of a mother-of-pearl, but 1hat Brahman is not the cause of the superimposition of these attributes on Itself, nor the author of ignorance.
Reply: Let it be so. Brahman is not the author of ignorance nor subject to error. But it is not admitted that there is any other conscious entity but Brahman which is the author of ignorance or subject tc error. Witness such Śruti texts as, ‘There is no ether knower but Him’ (III. vii. 23), ‘There is no other knower but This' (III. viii. 11), ‘Thou art That’ (Ch. VI. viii. 7), ‘It knew only Itself as, “I am Brahman”’ (this text), and ‘He (who worships another god thinking), “He is one, and I am another,” does not know’ (Ibid.). And the Smṛtis: ‘(Living) the same in all beings’ (G. XIII. 27), ‘I am the self, O Arjuna (dwelling in the minds of all beings)’ (G. X. 20), [Page 150] and ‘(Wise men are even-minded) to a dog as well as a Caṇḍāla’ (G. V. 18). And the Vedic Mantras: ‘He who (sees) all beings (in himself)’ (Iś. 6), and ‘When all beings (have become his self)’ (Iś. 7).
Objection: In that case scriptural instruction is useless.
Reply: Quite so, let it be, when the truth has been known.
Objection: But it is also useless to know the truth.
Reply: No, for we see it removes ignorance.
Objection: If there is unity, this removal of ignorance also is impossible.
Reply: Not so, for it contradicts experience.
We actually see that the knowledge of unity alone dispels ignorance. If you deny an observed fact, saying it is impossible, you would be contradicting experience, a thing which nobody will allow. Nor is there any question of impossibility with regard to an observed fact, because it has actually been observed.
Objection: But this observation also is impossible.
Reply: There also the same logic will apply.
Objection: ‘One indeed becomes good through good work’ (III. ii. 13), ‘It is followed by knowledge, work’ (IV. iv. 2), ‘The individual self, the Puruṣa, is a thinker, knower and doer’ (Pr. IV. 9)—from such Śruti and Smṛti texts as well as from reason we know that there is a transmigrating self other than and distract from the Supreme Self. And the latter is known to be distinct from the former from such Śruti texts [Page 151] as the following: ‘This (self) is That which has been described as “Not this, not this,”’ (III. iv. 26), ‘It transcends hunger etc.,’[29] ‘The Self that is sinless, undecaying, deathless’ (Ch. VIII. vii. 13), and ‘Under the mighty rule of this Immutable’ (III. viii. 9). Again, in the systems of logic (Vaiśeṣika and Nyāya) advocated by Kaṇāda and Gautama, the existence of a God distinct from the transmigrating self is established through argument. That the latter is different from God is clearly seen from its activity due to its desire to get rid of the misery of relative existence. Also from such Śruti and Smṛti texts as: ‘It is without speech and without zeal’ (Ch. III. xiv. 2), and T have no duties, O Arjuna’ (G. III. 32). And from the distinct mention of God as the object of search and the individual self as the seeker, in such (Śruti) passages as: ‘That is to be sought, and That one should desire to realise’ (Ch. VIII. vii. 1, 3), ‘Knowing It one is not touched (by evil action)’ (IV. iv. 23), ‘The knower of Brahman attains the highest’ (Tai. II. i. 1), ‘It should be realised in one form only’ (IV. iv. 20), ‘He, O Gārgī, who without knowing this Immutable’ (III. viii. 10), ‘Knowing It alone the sage’ (IV. iv. 21), and ‘The syllable Om is called the bow, the individual self the arrow, and Brahman the target' (Mu. II. ii. 4). Another reason for the difference is the mention of a journey, particular routes and a destination for a seeker of liberation. If there is no difference, who should make the- journey and how, and in the absence of this, two particular routes, viz. the southern and northern, are meaningless, and the destination as [Page 152] well. But if the individual self is different from the Supreme Self, all this would be consistent. Also they must be different because the scriptures prescribe the two means, viz. rites and knowledge. If the individual self is different from Brahman, the teaching of rites and knowledge as means to prosperity and liberation respectively may aptly apply to it, but not to God, for the objects of His desire are eternally attained. Therefore it is proper to understand the word ‘Brahman’ in the sense of a man aspiring to be Brahman.
Reply: No, for then instruction about Brahman would be useless. If a man subject to transmigration and only aspiring to be identified with Brahman became all by knowing himself to be Brahman, although he was not It, then instruction about the Supreme Brahman is certainly useless, for he attained identity with all as a result of knowing only the transmigrating self, and the knowledge of the Supreme Brahman is never utilised[30] for attaining human ends.
Objection: The instruction is only meant for the man subject to transmigration, so that he may practise the meditation based on resemblance[31] with regard to Brahman as, ‘I am Brahman.’ For if he does not fully know the nature of Brahman, with what can be identify himself in fancy as, ‘I am Brahman’? This [Page 153] meditation based on resemblance is possible only when the characteristics of Brahman are fully known.
Reply: Not so, for we know that the words ‘Brahman’ and ‘self’ are synonymous, being used thousands of times in co-ordination in such texts as the following: ‘This self is Brahman’ (II. v. 19), ‘The Brahman that is immediate and direct’ (III. iv. 1-2; III. v. 1), The Self (that is sinless)’ (Ch. VIII. vii. i, 3), ‘It is truth, It is the Self’ (Ch. VI. viii. 7 etc.) and ‘The knower of Brahman attains the highest’ (Tai. II. i. 1), these last introductory words (to Tai. II.) being shortly after followed by the words, ‘From this Self,’ etc. (Ibid.). The meditation based on resemblance is performed when the two things concerned are different, not when they are identical. And the sentence, ‘This all is the Self’ (ii. iv. 6). shows the unity of the Self under consideration that is to be realised. Therefore the Self cannot be regarded as Brahman through the meditation based on resemblance.
Nor do we see any other necessity for instruction about Brahman, for, the Śruti méntions identification with It in the passages, ‘(He who) knows (that Supreme) Brahman becomes Brahman' (III. ii. 9), 'You have attained That which is free from fear, O Janaka’ (IV. ii. 4), and ‘He... becomes the fearless Brahman' (IV. iv. 25). If the meditation based on resemblance were meant, this identity would not take place, for one thing cannot become another.
Objection: On the strength of scriptural statements, even the meditation based on resemblance may lead to identity.
Reply: [Page 154] No, for this meditation is only an idea. And knowledge, as we have said, only removes the false notion, it does not create anything. Nor can a scriptural statement impart any power to a thing. For it is an accepted principle that the scriptures are only informative, not creative.[32] Besides, in the passage, ‘This Self has entered into these bodies,’ etc. (I. iv. 7), it is clear that the Supreme Self alone has entered. Therefore the view that the word ‘Brahman’ means a man who will be Brahman, is not a sound one. Another reason is that it contradicts the intended' meaning. The desired import of this whole Upaniṣad is the knowledge that Brahman is without interior or exterior and homogeneous like a lump of salt, as is known from the assertion made at the end of both Madhu and Muni Kāṇḍas,[33] ‘This is the teaching’ (II. v. 19), and ‘This much indeed is (the means of) immortality, my dear’ (IV. v. 15). Similarly, in the Upaniṣads of all recensions the knowledge of the unity of Brahman (self) is the certain import. If, therefore, the passage in question is interpreted to mean that the transmigrating self, which is different from Brahman, knew itself, the desired meaning of the Upaniṣads would be contradicted. And in that case the scripture, having its beginning and end not tallying with each other, would be considered inconsistent. Moreover, the name would be out of place. In other words, if in the passage, ‘It knew only Itself,’ the word ‘It’ is supposed to refer to [Page 155] the transmigrating self, the name given to the knowledge would not be ‘the knowledge of Brahman’ for then, ‘It knew only Itself,’ should mean that the transmigrating self was the entity that was known.
Objection: Suppose we say that the word ‘Self’ iefers to an entity other than the knower.[34]
Reply: Not so, for there is the specification, ‘I am Brahman,’ If the entity known weie other than the knower, the specification should be, ‘It is Brahman,’ or ‘That is Brahman,’ and not T am Brahman.’ But since it is, ‘I am Brahman,’ and there is the assertion, ‘It knew only Itself,’ we know it for certain that the self is Brahman. And then only the name ‘the knowledge of Brahman’ would be appropriate, not otherwise. In the other case it would be ‘the knowledge of the transmigrating self.’ Nor can the same entity really be both Brahman and not Brahman, just as the sun cannot be both bright and dark, for these are contradictory features. And if both were the cause of the name, there should not be the sure appellation 'the knowledge of Brahman.’ It should then be ‘the knowledge of Brahman and of the transmigrating self.’ Nor in proceeding to expound the knowledge of Truth should one present the reality as an absurdity, like a woman, for instance, being one-half old and one-half young. That will only cause doubt in the mind of the listener. Whereas it is sure knowledge that is regarded as leading to liberation, the goal of human life, as is evidenced by the following Śruti and Smṛti [Page 156] texts: ‘He who really has (the conviction that he will attain the conditioned Brahman after, death) and has no doubt about it (does attain him)’ (Ch. III..xiv. 4), and ‘The doubting man perishes’ (G. IV. 40). Hence one who wishes to do good to others should not use expressions of a doubtful import.
Objection: To think that Brahman, like us, is a seeker of liberation, is not proper, and that is what we see in the passage, ‘It knew only Itself.... Therefore It became all.’
Reply: Not so, for by saying this you will be flouting the scriptures.. It is not our idea, but that of the scriptures Hence your fling hits them. And you who wish to please Brahman should not give up tfie real  meaning of the scriptures by fancying things contrary to it. Nor should you lose your patience over this much only, for all plurality is but imagined in Brahman, as we know from hundreds of texts like the following: ‘It should be realised in one form only' (IV. iv. 20), ‘There is no difference whatsoever in Brahman’ (IV. iv. 19; Ka. IV..11), ‘When there is duality, as it were’ (II. iv. 14; IV. v. 15), and ‘One only without a second’ (Ch. VI. ii. 1). Since the whole phenomenal world is imagined in Brahman alone and is not real, you say very little when you condemn this particular idea as improper.
Therefore the conclusion is that the word ‘Brahman’ refers to that Brahman which projected the universe and entered into it.
This, the Brahman (self) that is perceived as being in this body, was indeed—this word is emphatic—[Page 157] Brahman, and all, in the beginning, even before realisation. But owing to ignorance it superimposes on itself the notion that it is not Brahman, and that it is not all, and consequently thinks, through mistake, that it is an agent, possessed of activity, the experiencer of its fruits, happy or miserable, and transmigrating. But . really it is Brahman different from all the foregoing and is a 11. Being somehow awakened by a merciful teacher who told it that it was not subject to transmigration, ‘It knew only Itself ,’ its own natural Self, that is, which is free from differentiations superimposed by ignorance. This is the meaning of the particle ‘eva’ (only).
Objection: Tell me, what is that natural Self which Brahman knew?
Reply: Do you not remember the Self? It has been pointed out as the one that entering into these bodies does the function of the Prāṇa, Apāna, Vyāna, Udāna and Samāna.[35]
Objection: You are describing It as one would describe a cow or a horse by simply saying, ‘It is a cow,’ or ‘It is a horse.’ You do not show the Self directly.
Reply: Well then, the Self is the seer, hearer, thinker and knower.
Objection: Here also you do not directly point out the nature of that which does the functions of seeing etc. Going is surely not the nature of one who goes, nor editing that of a cutter.
Reply: In that case the Self is the seer of sight, [Page 158] the. hearer of hearing, the thinker of thought and the knower of knowledge.
Objection: But what difference does it make in the seer? Whether it be the seer of sight or of a jar, it is but the seer under all circumstances. By saying ‘The seer of sight’ you are simply stating a difference as regards the object seen. But the seer, whether it be the seer of sight or of a jar, is just the same.
Reply: No, for there is a difference, and it is this: If that which is the seer of sight is identical with that sight, it always visualises the latter, and there is never a time when sight is not visualised by the seer. So the vision of the seer must be eternal. If it were transitory, then sight, which is the object visualised, may sometimes not be seen, as a jar, for instance, may not always be perceived by the transitory vision. But the seer of sight never ceases to visualise sight like that.
Objection: Has the seer then two kinds of vision, one eternal and invisible, and the other transitory and visible?
Reply: Yes. The transitoty vision is familiar to us, for we see some people are blind, and others are not. If the eternal vision were the only one in existence, all people would, be possessed of vision. But the vision of the seer is an eternal one, for the Śruti says, ‘The vision of the witness can never be lost’ (IV. iii. 23). From inference also we know this. For we find even a blind man has vision consisting of the impressions of a jar. etc. in dreams. This shows that the vision of the seer is not lost with the loss of the other [Page 159] kind of vision. Through that unfailing eternal vision, which is identical with It and is called the self-effulgent light, the Self always sees the other, transitory vision in the dream and waking states, as idea and perception respectively, and becomes the seer of sight. Such being the case, the vision itself is Its nature, like the heat of fire, and there is no other conscious (or unconscious) seer over and above the vision, as the Vaiśeṣikas maintain.
It, Brahman, knew only Itself, the eternal vision, devoid of the transitory vision etc. superimposed on It.
Objection: But knowing the knower is self-contradictory, for the Śruti says, ‘One should not try to know the knower of knowledge’ (III. iv. 2).
Reply: No, this sort of knowledge involves no contradiction. The Self is indeed known Ihus, as ‘the seer of sight.’ Also it does not depend on any other knowledge. He who knows that the vision of the seer is eternal, does not wish to see It in any other way. This wish to see the seer automatically stops because of its very impossibility, for nobody hankers after a thing that does not exist. And that sight which is itself an object of vision does not dare to visualise the seer, in which case one might wish to do it. Nor does anybody want to see himself. Therefore the sentence, ‘It knew only Itself,’ only means the cessation of the superimposition of ignorance, and not the actual cognising of the Self as an object.
How did It know Itself? As ‘I am Brahman, the Self that is the seer of sight.’ ‘Brahman’ is That which is immediate and direct, the Self that is within all, beyond hunger and the like, described as ‘Not this,[Page 160] not this,’ neither gross nor subtle, and so on. ‘I am, as you[36] said, That and no other, not the transmigrating self.’ Therefore, from knowing thus, It, Brahman, became all. Since by the cessation of the superimposed notion of not being Brahman, its effect, the notion of not being all, was also gone, therefore It became all. Hence men are justified in thinking that through the knowledge of Brahman they would become all. The question, ‘Well, what did that Brahman know by which It became all?’ has been answered: ‘This was indeed Brahman in the beginning. It knew only Itself as, “I am Brahman.” Therefore It became all.’
And whoever among the gods knew It, the Self, in the manner described above, that awakened self also became That, Brahman. And the same with sages and men. The words ‘gods’ etc. are used froin the conventional point of view, not from that of the vision of Brahman. We have already said that it is Brahman which has entered everywhere, as set forth in the passage, ‘That Supreme Being first entered the bodies’ (II. v. 18). Hence the words ‘gods’ etc. are used from the conventional standpoint determined by the limiting adjuncts such as the body. Really it was Brahman which was in those divine and other bodies even before realisation, being only looked upon as something else. It knew only Itself and thereby became all.
To strengthen the import of the passage that this knowledge of Brahman leads to identity with all, the Śruti quotes some Mantras. How? The sage Called [Page 161] Vāmadeva, while realising this, his own self, as identical with That, Brahman, knew, from this realisation of Brahman, i.e. in that state of realisation of the ideṅtity of the self and Brahman, visualised these Mantras, ‘I was Manu, and the sun,’ etc. (Ṛ. IV. xxvi. i). The expression, ‘While realising this (self) as That’—Brahman—refers to the knowledge of Brahman. And the words, ‘I was Manu, and the sun/ refer to its result, identity with all. By the use of the form,[37] ‘While realising’ It he attained this result, viz. identity with all, the Śruti shows that liberation is attainable through the aid of the knowledge of Brahman, as in the expression, ‘While eating he is getting satisfaction.’ Someone may think that the gods, who are great, attained this identity with all through the knowledge of Brahman because of their extraordinary power, but those of this age, particularly men, can never attain it owing to their limited power. In order to remove this notion the text says: And to this day whoever, curbing his interest in external things, in like manner knows It, the Brahman under consideration which has entered into all beings and is indicated by the functions of seeing etc., i.e. his own Self, as, ‘I am Brahman,’ which is untouched by the attributes of the phenomenal universe, is without interior or exterior and absolute, by discarding the differences superimposed by the false notion created by limiting adjuncts, becomes all this, owing to his notion of incompleteness—the effect of ignorance—being removed by the knowledge of Brahman. For there is no difference [Page 162] as regards Brahman or the knowledge of It between giants like Vāmadeva and the human weaklings of to-day. But, one may suppose, the result of the knowledge of Brahman may be uncertain in the case of the present generation. This is answered as follows: Even the gods, powerful as they may be, cannot prevail against him, the man who has known Brahman in the manner described above—have not the capacity to stop his becoming Brahman and all, much less others.
Objection: Is there any ground for supposing that the gods and others can thwart the attainment of the results of the knowledge of Brahman?
Reply: Yes, beacuse men are indebted to them. The Śruti text, (Every Brāhmaṇa—twice-born—by his very birth is indebted) to the sages in respect of continence, to the gods in respect of sacrifices, and to the Manes in respect of progeny’ (Tai. S. VI. iii. 10. 5), shows that a man by his very birth is under certain obligations. And we know it from the illustration of animals (in this text). There is also the text, ‘Now this self (the ignorant man),’ etc. (I. iv. 16), describing him as an object of enjoyment for all, which shows that it is reasonable to suppose that the gods, in order to maintain their livelihood, may hinder men, who are dependent, jfrom attaining immortality, as creditors do with their debtors. The gods also protect their animals like their own bodies, for the Śruti will show that each man being equivalent to many animals, the gods have a great source of livelihood in the rites performed by him. It will presently be stated, ‘Therefore it is not liked by them that men should know this’ (this text), [Page 163] and ‘Just as one wishes safety to one's body, so do all beings wish safety to him who knows it as such’ (I. iv. 16). From the mention of dislike and safety we understand that the gods think that when a man attains the knowledge of Brahman, he will cease to be their object of enjoyment and their animal, for his dependence will end. Therefore the gods may very well hinder a prospective knower of Brahman from attaining the results of the knowledge of Brahman, for they are also powerful.
Objection: In that case the gods may find it like drinking a beverage to obstruct the fruition of results in other spheres too, viz. rites. Well, it would shake one’s faith in the performance of the means of achieving prosperity and liberation. Similarly God also, being of inscrutable power; can put obstacles, as also time, action, sacred formulae, herbs and austerities, which, as we know from the scriptures as well as experience, can help or hinder the fruition of results. This too would shake one’s faith in the performance of scriptural rites.
Reply: Not so, for all things spring from definite causes, and we also see variety in the universe. Both these will be inconsistent if things happen spontaneously. Since it is the accepted view of the Vedas, Smṛtis, reasoning and tradition that happiness, misery, and the like are the outcome of one’s past work, the gods, or God, or time by no means upset the results of work, for these depend on requisite factors. Work, good or bad, that men do cannot come into being without the help of factors such as the gods, time and God, and even if it did, it would not have the power [Page 164] to produce results, for it is the very nature of work to spring from many causes such as the different factors. Therefore the gods, God and others being auxiliaries to work, there is nothing to shake our faith in the attainment of its results.
Sometimes also (in the matter of thwarting) they have to depend on the past work of men, for its inherent power cannot be checked. And there is no fixity about the relative predominance of past work, time, destiny and the nature of things etc.; it is inscrutable, and hence throws people into confusion. Some, for instance, say that in bringing about results one’s past work is the only factor. Others say it is destiny. A third group mentions time. Still others say if is the nature of things etc. While yet another group maintains it is all these things combined. Regarding this the Vedas and Smṛtis uphold the primacy of past work, as in the passage, ‘One indeed becomes good through good work and evil through evil work’ (III. ii. 13), and so on. Although one or other of these at times gains ascendancy in its own sphere over the rest, whose potential superiority lies in abeyance for the time being, yet there is no uncertainty about work producing results, for the importance of work is decided by the scriptures as well as reason.[38]
Nor (can the gods check the result of knowledge), for the realisation of Brahman, which is this result, consists in the mere cessation of ignorance. It has, been suggested that the gods may thwart the attainment [Page 165] of Brahman, which is the result expected from the knowledge of It; but they do not have that power. Why? Because this result, the attainment of Brahman, immediately follows the knowledge. How? As in the world a form is revealed as soon as the observer’s eye is in touch with light, similarly the very moment that one has knowledge of the Supreme Self, ignorance regarding It must disappear. Hence, the effects of ignorance being impossible in the presence of the knowledge of Brahman, like the effects of darkness in the presence of a lamp, whom should the gods thwart and by what means, for is not the knower of Brahman the self of the gods? This is what the text says: 'For he,the knower of Brahman, becomes their self, the reality of these gods, the object of their meditation, the Brahman that is to be known from all scriptures, simultaneously with the knowledge of Brahman, since, as we have said (p. 140), the only obstruction of ignorance vanishes then and there, like a mother-of-pearl mistaken for a piece of silver becoming itself again. Hence the gods cannot possibly try to stand against their own self. They succeed in their effort to put obstacles only in the case of one who seeks a result uhich is other than the Self and is separated by space, time and causation, but not with regard to this sage, who becomes their self simultaneously with the awakening of knowledge, and is not separated by space, time and causation, for there is no room for opposition here.
Objection: In that case, since there is not a stream of consciousness about knowledge (of Brahman), and since we see that a consciousness of an [Page 166] opposite nature together with its effects persists, let us say that only the last[39] consciousness of the Self removes ignorance, and not the first one.
Reply: No, for your ground of inference will be falsified on account of the first. If the first consciousness of the Self does not remove ignorance, neither will the last, for they are alike consciousness of the Self.
Objection: Well then, let us say, it is not the isolated consciousness that removes ignorance, but that which is continuous.
Reply: Not so, for there cannot be a continuity, since it would be broken by thoughts of self-preservation etc. So long as these crop up, there cannot be an unbroken stream of consciousness about knowledge, for the two are contradictory.
Objection: Suppose the latter continues till death to the exclusion of the former.
Reply: Not so, for the uncertainty about the requisite number of thoughts to make up that stream would be open to the charge of making the meaning of the scriptures indefinite. In other words, there being nothing to determine that so many thoughts would make up a stream that will remove ignorance, it would be impossible to determine the meaning of the scriptures, which is not desirable.
Objection: The meaning is quite definite, for in so far as it is a stream of consciousness, it will remove ignorance.
Reply: No, for there is no difference between the first and the last stream of consciousness. There [Page 167] being nothing to determine whether it is the first stream of consciousness about knowledge that removes ignorance or the last one ending with the moment of death, they too' would be open to those two charges already mentioned with regard to the first and last thoughts.
Objection: Well then, let us say that knowledge does not remove ignorance.
Reply: Not so, for the Śruti says, ‘Therefore It became all,’ as also, ‘The knot of the heart is broken,' etc. (Mu. II. ii. 8), ‘Then what delusion can there be?' (Iś. 7), and so on.
Objection: These may be mere eulogies.
Reply: No, for then the Upaniṣads in all the recensions would be classed as such, for they have just this one aim.
Objection: Suppose we say that they are but eulogies, for they deal with the self which is already known through perception.[40]
Reply: No, for we have already refuted that contention.[41] Also we have said that knowledge produces palpable iesults, viz. the cessation of such evils as ignorance, grief, delusion and fear (p. 134). Therefore there can be no question about knowledge removing ignorance, whether it be first or last, continuous or non-continuous, for knowledge culminates in producing the cessation of ignorance and other evils. Any consciousness that produces this result, whether first or last, continuous or non-continuous, is knowledge [Page 168] according to us. Hence there is no scope whatsoever for any objection.
You said, the first consciousness does not remove ignorance, because we see that a consciousness of an opposite nature to knowledge together with its effects persists. This is wrong, for the residue of Prārabdha work is the cause of the persistence of the bodv after knowledge. In other words, that resultant of past work which led to the formation of the present body (Prārabdha), being the outcome of false notions[42] and the evils (of attachment etc.), is able to bear fruit only as such, i.e. as coupled with those notions and evils; hence until the body falls, it cannot but produce, as part of one’s experience of the results of past work, just so much of false notions and the evils of attachment etc., for the past work that made this body has already begun to bear fruit and must run its course like an arrow that has been shot. Therefore knowledge cannot stop that, for they are not contradictory. What does it do then? It stops the effects of ignorance which are contradictory to it and are about to spring up from (the ignorance lying in) the self, which is the substratum of that knowledge, for they have not yet appeared. But the other is past.
Moreover, false notions do not arise in a man of realisation, for there is then no object for them. Whenever a false notion arises, it does so on account of a certain similarity of something to another,without ascertaining the particular nature of that thing, as when a mother-of-pearl is mistaken for a piece of silver. [Page 169] And this can no more happen to one who has ascertained the particular nature of that thing, for the source of all false notions (that cursory resemblance) has been destroyed; as they no more appear when a right perception of the mother-of-pearl, for instance, has taken place. Sometimes, however, memories due to the impressions of false notions antecedent to the dawning of knowledge, simulating those notions, suddenly appear and throw him into the error of regarding them as actual false notions; as one who is familiar with the points of the compass sometimes all of a sudden gets confused about them. If even a man of realisation comes to have false notions as before, then faith in realisation itself being shaken, no one would care to understand the meaning of the scriptures, andall evidences of knowledge would cease to be such, for then there would be no distinction between things that are valid evidences and those that are not. This also answers the question why the body does not fall immediately after realisation. The destruction of actions done before, after and at the time of realisation as well as those accumulated in past lives—actions that have not yet begun to bear fruit—is proved by the very negation of obstructions to the attainment of results in the present text, as also from such Śruti texts as the following: ‘And his actions are destroyed’ (Mu. II. ii. 8), ‘It takes him only so long (as he does not give up his body)’ (Ch. VI. xiv. 2), ‘All demerits are burnt up’ (Ch. V. xxiv. 3), 'Knowing It one is not touched by evil action’ (IV. iv. 23), ‘He is never overtaken by these two thoughts (of having done good and evil acts)’ (IV. iv. 22), 'Actions done pr omitted do not [Page 170]trouble him’ (Ibid.), ‘(Ṛemorse for doing evil and not doing good) does not trouble him’ (Tai. II. ix.), and ‘He is not afraid of anything’ (Ibid.). Also from such Smṛti texts as the following: ‘The fìre of knowledge reduces all actions to ashes’ (G. IV. 37).
The objection that he is tied up by his obligations (to the gods etc.) is not valid, for they concern an ignorant man. It is he who is under those obligations, for he can be presumed to be an agent and so forth. It will be said later on, ‘When there is something else, as it were, then one can see something’ (IV. iii. 31). These last words show thaf the acts of seeing etc. together with their results, which are dependent on many factors created by ignorance, are possible only in the state of ignorance, when the Self, the Reality that has no second, appears as something else, like a second moon when one has got the disease of double vision (Timira). But the text, ‘Then what should one see and through what?’ (II. iv. 14; IV. v. 15), shows that work is impossible in the state of knowledge, when the illusion of manifoldness created by ignorance has been destroyed. Therefore the indebtedness in question belongs only to an ignorant man, for whom it is possible to work, and to none else. We shall show this at length while dealing with passages that are yet to be explained.
As, for instance, here. While he, one who is not a knower of Brahman, who worships another god, a god different from himself, approaches him in a subordinate position, offering him praises, salutations, sacrifices, presents, devotion, meditation, etc., thinking, ‘He is one, non-self, different from me, and I am [Page 171] another, qualified for rites, and I must serve him like a debtor’—worships him with such ideas, does not know the truth. He, this ignorant man, has not only the evil of ignorance, but is also like an animal to the gods. As a cow or other animals are utilised through their services such as carrying loads or yielding milk, so is this man of use to every one of the gods and others on account of his many services such as the performance of sacrifices. That is to say, he is therefore engaged to do all kinds of services for them.
The scriptural rites, with or without the accompaniment of meditation, which this ignorant man, for whom the divisions of caste, order of life and so forth exist, and who is bound to those rites, performs, lead to progress beginning with human birth and ending with identity with Hiraṇyagarbha. While his natural. activities, as distinguished from those prescribed by the scriptures, lead to degradation beginning with the human birth itself and ending with identity with stationary objects. That it is so we shall explain in the latter part of this chapter beginning with, ‘There are indeed three worlds’ (I. V. 16), and continuing right up to the end. While the effect of knowledge (meditation) has been briefly shown to be identity with all. The whole of this Upaniṣad is exclusively devoted to showing the distinction between the spheres of knowledge and ignorance. We shall show that this is the import of the whole book.
Since it is so, therefore the gods can thwart as well as help an ignorant man. This is being shown: As inthe world many animals such as cows or horses serve a man, their owner and controller, so does each[Page 172] ignorant man, equivalent to many animals, serve the gods. This last word is suggestive of the Manes and others as well. He thinks, ‘This Indra and the other gods are different from me and are my masters. I shall worship them like a servant through praises, salutations, sacrifices, etc., and shall attain as results prosperity and liberation granted by them. Now, in the world, even if one animal of a man possessing many such is taken away, seized by a tiger, for instance, it causes great anguish.Similarly what is there to wonder at if the gods feel mortified when a man, equivalent to many animals, gets rid of the idea that he is their creature, as when a householder is robbed of many animals? Therefore it is not liked by them, these gods—what?— that men should somehow know thistruth of the identity of the self and Brahman. So the revered Vyāsa writes in the Anugītā, ‘The world of the gods, O Arjuna, is filled with those who perform rites. And the gods do not like that mortals should surpass them’ (Mbh. XIV. xx. 59). Hence as men try to save animals from being seized by tigers etc., so the gods seek to prevent men from attaining the knowledge of Brahman lest they should cease to be their objects of enjoyment. Those, however, whom they wish to set free, they endow with faith and the like; while the opposite class they visit with lack of faith etc. Therefore a seeker of liberation should be devoted to worshipping the gods, have faith and devotion, be obedient (to the gods) and be alert about the attainment of knowledge or about knowledge itself. The mention of the dislike of the gods is an indirect hint at all this.
[Page 173] In the sentence, ‘The Self alone is to be meditated upon’ (I. iv. 7) the gist[43] of the scriptures has been put in a nutshell. In order to explain it, its relation,[44] and utility have also been stated in the eulogistic passage, ‘They say: Men think,’ etc. (I. iv. 9). And that ignorance is the cause of one’s belonging to the relative plane has been stated in the passage, ‘While he who worships another god,’ etc. (I. iv. 10). There it has been said that an ignorant man is indebted and dependent like an animal, having to do duties for the gods etc. What is the cause of their having to do those duties? The different castes and orders of life. The following paragraphs are introduced in order to explain what these castes are, because of which this dependent man is bound to the rites connected with them, and transmigrates. It is to explain this in detail that the creation of Indra and other gods was not mentioned immediately after that of Fire. This last, however, was described to complete the picture of creation by Virāj. It should be understood that this creation of Indra and other gods also belongs to that, being a part of it. It is being described here only to indicate the reason why the ignorant man alone is qualified for the performance of rites.
 The gist of the brahmakandika
Brahman becomes everything by knowing itself.
Brahman alone is jivatma during ajnana avastha and hence when jivatma gains knowledge who is gaining knowledge  - brahman alone is gaining knowledge.

Who is ajnani jiva? Brahma Who is samsari? Brahman
Brahma eva avidya samsarati
Brahma eva avidya avasthayam samsari jivatma ityuchyate; shishyo bhavati; shravanam karoti; tad brahmaiva upadeshat shrnoti tasmat brhamiva janaati aham bramasmi iti; jnana avasthayam tad brahmaiva sarvam abhavat. That Brahman alone is a samsari, becomes a student when he finds a Guru, does shravanam and thus Brahman alone gains the knowledge aham brahmasmi and with this knowledge Brahman alone then becomes all

One and the same Brahman is called jiva during ajnana avastha and as Brahman during jnana avastha.

Upanishad talks about ajnana avastha and so assumes we are all now jnanis. Assuming this condition we read this mantra and only then it makes sense...
Agre - in the past - referring to ajnana avastha, Brahma alone was here Idam. Idam jeevatma avastha. chaitanyam in mind as sakshi obtaining in shareeram given name kshetrajna - this is the idam that was brahma alone.
Now after idam - tat - that jivatma brahman atmanam aved came to know itself And with this knowledge sarvam abhavat that Brahman Itself became everything
During ignornace Brahman was everything
Because of ignorance sarvatvam was not known and in its place asarvatvam was there. Asaravatvam was limitation and this superimposed limitation goes away with knowledge and leads to sarvatvam.

Here Shankara enters into a debate with Bhrtrprapancha who had written a commentary on this mantra.

Here Bhrtrprapancha idam refers to jivatma who is samsari and ignorant and this jivatma is going to become Brahman later after he gets knowledge. Since he is going to become Brahman later now itself Upanishad calls him Brahman.   
This jivatma as a result of aham brahmasmi knowledge attains sarvatma bhava and becomes Brahman. 

This is Bhrtrprapanchas view
He supports this with reasons
Jivatma during ignorance is different from Brahman as Shruti clearly says he "became" brahman.
Shruti also described Brahman and clearly differentiates by saying all virtues satykakama satyasankalpa sarvavyapi sarvaniyanta etc
And jivatma is clearly a samsari - alpajnah;  carried here and there because of power of karma. So he has to become paramatma only later
Scirptures also say Paramatma is something to be attained sa anveshTavyah, sa vijnjAsitavyah – ChAndogya. 8.7.1 He is to be searched for; so if jivatma has to search for Paramatma he has to be necessarily  be different
Third reason he gives- all philosophers agree that Paramatma is different from Jivatma. In tarka sangraha atma is of two types - one is Jivatma and Paramatma. In yogasutra Ishwara is described as different from jiva.
Fourth - anubhava or experience also shows that jivatma is a samsari because he experiences sorrow etc.

So Shankara has to refute these four main arguments.

First he takes the sentence tadātmānamevāvet aham brahmāsmīti tasmāttatsarvamabhavat
which means Atma knew itself and he points out that as per Bhrtrprapancha if this is taken to be separate jivatma then it means Jivatma knew itself as jivatma before. That means after knowing "I am jivatma" he gets sarvam. Shankra questions how can you call this brahmavidya? If jivatma jnana alone is required for sarvam then what need is there to know Paramatma. Discussion on Brahman becomes redundant. Brahmavidya upadesha vyatya.
If BP argues the 1st brahman refers to jivatma. the 2nd brahman i.e. aham brahmasmi.. refers to Paramatma. Now Brahmavidya becomes relevant, is it not? Hence as a result of jivatma of knowing aham brahmasmi becomes sarvam
Shankara counters saying - aham brahmasmi knowledge comes to jivatma. that means aham jivatma paramatma asmi. Now if jivatma is different from paramatma then can he ever say aham brahmasmi? It will be bhranti jnanam
BP further counters. Ok I accept that it is wrong knowledge. Even though it is wrong it is willingly entertained as a upasana. Every upasana is based on erroneous idea. Nonfactual idea. When I look upon saligrama as Vishnu it is erroneous idea - saligrama is jadam Vishnu is chetanam. Prayer goes not to stone but goes to Vishnu. But still we do the upasana we invoke or imagine Vishnu in saligrama. Every upasana is nonfactual Every error is nonfactual
When it is born of ignorance it is bhranti or error
When it is done knowingly it is upasana.
BP here says we should willingly imagine or visualize or imagine that. Then law tam yatha upasate tad bhavati what one upasana does he becomes that.
Shankara says upasana can never lead to limitless Brahman. This law can only apply to limited objects parichinna vastu.
Thus the only correct interpretation is that during ignorance also jivatma is Paramatma only but there is a superimposition of limitation abrahmabhava adhyasa 
Veda differentiates jivatma and paramatma due to seeming difference based on adhyasa.
And solution for this erroneous imagination is knowledge - with knowledge the imaginary or erroneous notion that i am not brahman goes away abrahma abhava adhyasa nivrtti.
Now BP comes back with a bigger objection.
He points out this interpret also has a problem

You say Brahman alone is there. Brahman alone was there in the beginning. That Brahman knew itself. When you say Brahman knew itself there are problems
One Brahman becomes associated with ignorance.

When a I know a tree. Tree is object. And I am the subject. Tree knowledge is located in me - jnanasya ashrayah. Object tree is jnanasta vishayah.
You can extend the same for ajnanam. When I am ignorant of a mango then also there is similarly vishayah and ashrayah.
Brahman knew itself - That means before this knowlege there must be ignorance. In this knowledge what is the object itself i.e. Brahman and subject is also Brahman. Also means when brahman was ignorant of itself before this knowledge, subject or ashrayah is Brahman and vishayah is also Brahman. Brahman ajnanasya ashraya and ajnanasya vishayah. How can Brahman be the object of ignorance it being svayam jyoti prakasah svatsiddhah - or more simply how can there be ignornace in Brahman and of Brahman. There are elaborate discussions elsewhere based on logic but here Shankara does not go to logic because BP is a astika and so he uses the Upanishad itself

How can Brahman be object of ignorance? Shankara says Veda says everyone should know Brahman and Brahman knowledge gives Moksha.Brahmavit apnoti param. (Taitt) Brahmveda Brahmaiva bhavati (Mundaka). If Shruti asks a person to know Brahman that means according to Shruti Brahman is a object of ignorance. The fact that Shruti wants to give knowledge of Brahman then by arthapati Brahman ignorance has to be a fact. Now what about locus?
Here also Shankra bases his argument on Shruti. Ajnana can only be in a chetana vastu. Only a conscious being can be ignorant or knowledgeable. Inert matter can never have ignorance. There is only one Chetana vastu sAkshi chetaH kevalo nirguNascha (Shvet Up), there is no other chetana vastu other than Brahman. So Brahman alone can be the ashraya of ignorance. That Brahman alone superimposed abrahmatvam seemingly and poornatvam seems to come with knowledge.

Lastly now BP raises another objection - kartr karma virodhah. subject object contradiction.
No process can have identical subject and object
Even atma anatma drg drysa viveka is based on this law alone. Subject can never be object.
Then how can Brahman know itself - how can Brahman be both object and subject.
Sankara says - Brahman can never know itself.

Therefore Brahman knows itself - means knows has to be "knows" - this knowing is not regular knowing which involves objectification or involves phala vyapti. Here knowing only means removal of false superimposition. Anatma tad dharma adhyaropa nivrtti eva atma jnanam
Brahman is ever evident as aham I . No mental process is required . no mental experience is required. Pratibodha viditam matam. Shruti negates the limitation. There is no subject object contradiction. And Shankara says his interpretation alone is in keeping with shruti yukti anubhava

With this mahavakya bhashyam is over. And this discussion can be connected with 9th mantra. How does Brahman become all. That question also is answered. Brahman "knows" itself and "becomes" everything.

Continuing:

तद्यो यो देवानाम् प्रत्यबुभ्यत स एव तदभवत्, तथार्षीणाम्, तथा मनुष्याणाम्; तद्धैतत्पश्यन्नृषिर्वामदेवः प्रतिपेदे, अहम् मनुरभवं सूर्यश्चेति । तदिदमप्येतर्हि य एवं वेद, अहम् ब्रह्मास्मीति, स इदं सर्वम् भवति, तस्य ह न देवाश्चनाभूत्या ईशते, आत्मा ह्येषां स भवति; 


In sarvatmabhava jnana - I am everything - and nothing is different from me and thus bheda buddhi is destroyed - notion of difference is destroyed. When the idea of difference or division is gone then samsara is also gone udaram antaram kurute (Taitt Up)


For doing Karmas many restrictions are mentioned - as karmas are based on varna and ashram. Benefit will accrue only if karma is appropriate for that varna
Jnana is not dependent on varna or ashrama. Whoever desires jnana can get it. Jnana is based on atma which is same in all. Karma is based on anatma. From atma standpoint atma is ever akarta. Anyone who desires knowledge and who has qualification to get this knowledge can get this knowledge. Even devas - who don't have right to karma and phala - have right to knowledge. 
Among the devas whoever yo yo gains this knowledge he becomes Brahman he becomes everything. He alone eva can get Moksha. Also similarly for Rishis and men. Upanisad now quotes a arthavada mantra to support this idea. Vamadeva Rshi knew this and having gained that knowledge declared - I am Manu, I am the Sun, I am everything. Upanisad here shows there's thus a precedence. Even devas cannot stop the liberation.
Moment a person gets knowledge liberation is definite.

Here Shankara takes up a small discussion.
Liberation is definite for a jnani - devas cannot obstruct.
If at all they want to obstruct they can obstruct the gain of knowledge.
They cannot obstruct moksha once jnana is obtained. There is no time gap between jnana and moksha.
After jnana if there is a gap or process involved in Moksha then only it is possible for Devas can interfere - but since jnanam eva moksha na tu jnanat moksha... jnana itself is liberation and moksha is at the very moment of rise of knowledge.