Shree Krishna in the Bhagavad Gita 2.12 states:
"There never was a time when I did not exist, nor you, nor any of these temporal kings. Nor will there be any time in future when all of us shall cease to be."
And the following is the commentary of Ramanujacharya on this verse:
“I, [Krishna] who am, as you know, the eternal Lord of all, was never non-existent, but have always existed. There never was a time when these Selves (jīvas) like you [and the others], who are subject to My sovereignty, did not exist. You have always existed, and 'all of us' — I and you, shall never cease to be 'in the future'; we shall always exist. Just as there is certainly no doubt that I, the Supreme Self and Lord of all, am eternal, likewise, you [and all others] who are embodied Jīvas, should never doubt your eternality either.” The foregoing teaching implies that the difference between the Lord who is the sovereign over all, and the individual jīvas; as also the differences among the individual jīvas themselves, are real. This has been declared by the Lord Himself because different terms like 'I', 'you', 'these', 'all' and 'we' have been used by the Lord while explaining the truth of eternality in order to remove the misunderstanding of Arjuna who is deluded by ignorance. As regards the doctrine of Bhaskara [and the Advaitins] that the above mentioned distinctions [between the Lord and jīvas, and between the jīvas themselves] are unreal and due to some limiting condition (Māyā) — it would be highly improper [for the Lord] to make reference to distinctions at the time of imparting the [ultimate] Truth. If we examine [Bhaskara's] theory of upādhi (adventitious limitation), which states that the apparent differences among jīvas are due only to the bodies (adventitious limitations), it must be admitted that discussion of differences is out of place when explaining the ultimate Truth, because according to the theory [of Bhaskara and the Advaitins] there are no such differences in reality. The inherent differences mentioned by the Lord are taught by the Veda also:— 'Eternal among eternals, the intelligent among the intelligent, the one among many who fulfils desires’ (Sve. Up. 6:13, Ka. Up. 2:2:13). The meaning of this text is: — ‘Among the eternal sentient beings who are countless, He, who is the Supreme Spirit fulfils the desires of all.' As regards the doctrine of the Advaitins that the perception of difference arises from ignorance (ajñāna or avidya) only, and is not actually real; [it may be pointed out that] the Supreme Being — whose comprehension must be perfect, free from all ignorance and its effects —must therefore have a direct cognition of the true nature of the ātman; comprised of eternal consciousness, and being without any differentiation and unchangeable. He therefore cannot possibly be aware of the so-called differences which arise from ignorance. It is, therefore, unimaginable that He would then engage Himself in activities such as teaching which are based entirely upon such a perception of differences arising from ignorance. It may be argued that the Supreme Being, though perfectly aware of non-duality, can still be aware of such difference which persists even after sublation. For example a burnt piece of cloth may continue to look like a cloth, and that such continued [perception] of the nullified does not cause Him bondage. Such a proposition is invalidated in the light of another analogy of a similar kind, namely, the perception of the mirage. When a mirage is realised to be what it is, one does not then persist in an attempt to fetch water there from. In the same way, even if the impression of difference persists after it has been nullified by the realisation of non-dualism, it cannot impel one to activities such as teaching; for the person to whom the instruction is to be imparted is discovered to be unreal. The idea is that just as the discovery of the non-existence of water in a mirage brings an end to all efforts to get water from it, so also when all duality is negated by enlightenment, no activity like teaching disciples etc., could take place. Nor is it acceptable that the Supreme Lord was at one time ignorant and obtained knowledge of non-duality through the Scriptures, and is still being subject to the continuation of the suppressed experiences. Such a contention contradicts the Veda (Śruti) and the Smrti (Canon Law): — 'He, who is all-knowing and all wise' (Mun.Up., 1.1.9); His supreme power is indeed revealed as varied and inherent, and consists of omniscience, omnipotence and action' (Sve. Up. 6.8); 'I know, Arjuna, all beings of the past, present and future but no one knows Me,' etc. (Gita 7:26). And again, if the perception of difference and distinction are said to persist even after the non-dual Self has been decisively realised, the question arises— to whom will the Lord and the succession of teachers of the tradition (Guru Parampara) impart the knowledge in accordance with their realisation? The question requires an answer. The realisation of non-duality cannot possibly coexist with the perception of differences. If the Advaitins reply using the Bimba-Pratibimba (the original and the reflection) argument that teachers give instructions to their own reflections in the form of disciples such as Arjuna, it is absurd. For, no sane person would attempt to give instructions to his own reflection seen in precious stone, the blade of a sword or a mirror, knowing, as he does, that they are non-different from himself! The theory of the persistence of the sublated is thus impossible to maintain, because the knowledge of the non-dual Self is supposed to destroy the very ignorance in which differences external to the Self are alleged based. 'The persistence of the sublated' does indeed occur in cases where the cause is the result of some physical defect such as the seeing of two moons, in impaired eyesight known as double-vision (diplopia). This double vision cannot be nullified by the right understanding that there is only one moon. Even though the perception of the two moons may continue, it is rendered inconsequential on the strength of strong contrary evidence. For, it will not lead to any activity based upon a real experience. But in the present context [in the case of Sri Krishna teaching Arjuna], the concept of difference — where both object and cause are admittedly unreal — is negated by the knowledge of reality. So the 'persistence of the sublated' is impossible. Thus, if the Supreme Lord and the succession of preceptors (guru-parampara) have attained the realisation of [a non-dual] reality, their perception of duality [after realisation] and activities such as teaching proceeding from such [non-dual] realisation, are impossible. If, on the other hand, the perception of difference persists because of the continuation of ignorance and its causes, then these teachers are themselves ignorant of the Truth, and they will be incapable of teaching the Truth. Moreover, as the preceptor has attained the realisation of the non-dual ātman and thereby overcome the ignorance obscuring Brahman and all the effects of such ignorance, there is no purpose in instructing the disciple. If it be argued that the preceptor and his teaching are just in the imagination of the disciple, the disciple and his knowledge are similarly the product of the imagination of the preceptor, and as such the ignorance in question cannot be overcome. If it is maintained that the disciple's knowledge, even though imaginary, overcomes ignorance etc., because it annuls the previous state of non-enlightenment, the same can be asserted of the preceptor's knowledge. The futility of such teachings is obvious. Enough of these unsound doctrines which have all thus been refuted!
How do Advaitins counter the above rebuttal by Ramanujacharya on Advaita Vedanta?
Update: Ramanujacharya also tries to refute Advaitic doctrine of absolute unity of the Jiva while commenting on Bhagavad Gita 5.16 (But to those whose ignorance is destroyed by Self-realisation, their enlightenment is supreme and illumines like the sun) where He says:
In the case of the enlightened ones, their delusion is destroyed by wisdom. This enlightenment arises from [studying] the teachings about the real nature of the ātman, and is then realized by daily practice. The purity of this wisdom is unsurpassed, and in the case of those Jīvas who regain the expansive consciousness that is natural to them, it is found to be unlimited and un-contracted and illumines everything like the sun.
The essential plurality of the Jīvas in their original state is expressly mentioned in connection with the enlightened or fully realized ones by the expression 'those' in the above text. In the beginning (Gita 2:12) it was said — “There never was a time when I did not exist, nor you, nor any of these kings of men. Nor will there be any time in future when all of us shall cease to be” — this statement is clarified here. Moreover, this plurality [of Jīvas] cannot be due to limiting factors imposed on a single universal ātman [as taught by the Advaitins]. For, as stated here, there is no residual trace of such limiting adjuncts (such as ignorance) for those that are fully enlightened, and yet still, they are described [by Krishna] as a plurality. Here consciousness is taught as an attribute inseparable from the essential nature of the Self, because a difference between the Self and its consciousness is indicated by the statement, 'Knowledge, in their case illuminates like the sun’. By the illustration of the sun, the relationship of the knower to its knowledge is likened to the luminous object and its luminosity. Therefore, it is appropriate to consider that one’s consciousness contracts through Karma, in the condition of Samsāra (transmigration) and expands in the stage of Mokṣa (liberation).
