sri-bhagavan uvaca
bahuni me vyatitani
janmani tava carjuna
tany aham´ veda sarvan?i
na tvam´ vettha parantapa

Translation of Bhagavad Gita 4.5

The Personality of Godhead said: Many, many births both you and I have passed. I can remember all of them, but you cannot, O subduer of the enemy!

Commentary by Sri A.C. Bhaktivedanta Swami Prabhupada of Gaudiya Sampradaya:

In the Brahma-samhita (5.33) we have information of many, many incarnations of the Lord. It is stated there:

advaitam acyutam anadim ananta-rupam
adyam purana-purusham nava-yauvanam ca
vedesu durlabham adurlabham atma-bhaktau
govindam adi-purusham tam aham bhajami

“I worship the Supreme Personality of Godhead, Govinda [Krishna], who is the original person—absolute, infallible, without beginning. Although expanded into unlimited forms, He is still the same original, the oldest, and the person always appearing as a fresh youth. Such eternal, blissful, all-knowing forms of the Lord are usually understood by the best Vedic scholars, but they are always manifest to pure, unalloyed devotees.”

It is also stated in Brahma-samhita (5.39):

ramadi-murtisu kala-niyamena tisthan
nanavataram akarod bhuvanesu kintu
krishnah svayam samabhavat paramah puman yo
govindam adi-purusham tam aham bhajami

“I worship the Supreme Personality of Godhead, Govinda [Krishna], who is always situated in various incarnations such as Rama, Nrisimha and many subincarnations as well, but who is the original Personality of Godhead known as Krishna, and who incarnates personally also.”

In the Vedas also it is said that the Lord, although one without a second, manifests Himself in innumerable forms. He is like the vaidurya stone, which changes color yet still remains one. All those multiforms are understood by the pure, unalloyed devotees, but not by a simple study of the Vedas (vedesu durlabham adurlabham atma-bhaktau). Devotees like Arjuna are constant companions of the Lord, and whenever the Lord incarnates, the associate devotees also incarnate in order to serve the Lord in different capacities. Arjuna is one of these devotees, and in this verse it is understood that some millions of years ago when Lord Krishna spoke the Bhagavad-gita to the sun-god Vivasvan, Arjuna, in a different capacity, was also present. But the difference between the Lord and Arjuna is that the Lord remembered the incident whereas Arjuna could not remember. That is the difference between the part-and-parcel living entity and the Supreme Lord. Although Arjuna is addressed herein as the mighty hero who could subdue the enemies, he is unable to recall what had happened in his various past births. Therefore, a living entity, however great he may be in the material estimation, can never equal the Supreme Lord. Anyone who is a constant companion of the Lord is certainly a liberated person, but he cannot be equal to the Lord. The Lord is described in the Brahma-samhita as infallible (acyuta), which means that He never forgets Himself, even though He is in material contact. Therefore, the Lord and the living entity can never be equal in all respects, even if the living entity is as liberated as Arjuna. Although Arjuna is a devotee of the Lord, he sometimes forgets the nature of the Lord, but by the divine grace a devotee can at once understand the infallible condition of the Lord, whereas a nondevotee or a demon cannot understand this transcendental nature. Consequently these descriptions in the Gita cannot be understood by demonic brains. Krishna remembered acts which were performed by Him millions of years before, but Arjuna could not, despite the fact that both Krishna and Arjuna are eternal in nature. We may also note herein that a living entity forgets everything due to his change of body, but the Lord remembers because He does not change His sac-cid-ananda body. He is advaita, which means there is no distinction between His body and Himself. Everything in relation to Him is spirit—whereas the conditioned soul is different from his material body. And because the Lord’s body and self are identical, His position is always different from that of the ordinary living entity, even when He descends to the material platform. The demons cannot adjust themselves to this transcendental nature of the Lord, which the Lord Himself explains in the following verse.

Commentary by Sri Vishvanatha Chakravarthi Thakur of Gaudiya Sampradaya:

In this verse, the Lord speaks with the intention to show that he instructs through the agency of his avataras.

I  appear as various  avataras,  and you  also  appear  as my companion at that time. I know, since I am omniscient, being the  Supreme lord.  You  do  not know,  since I  cover your knowledge  for  fulfilling the purpose of my pastimes. With knowledge covered, O afflicter of the enemy, you afflict (tapa) the enemies (param) by thinking of yourself as the son of Kunti a ksatriya, during in this life.

Commentary by Sri Ramanuja of Sri Sampradaya:

4.5 The Lord said — By this, the reality of the Lord’s birth is declared in the sentence, ‘Many births of Mine have passed.’ ‘So is it with you’ is added by way of illustration. The mode of incarnation, the reality of His body and the cause of His birth are explained in the following verse.

Commentary by Sri Sridhara Swami of Rudra Sampradaya:

Lord Krishna replying informs Arjuna that He instructed Visvavan in a different form then the one Arjuna is beholding at that moment and that by His supreme potency, immutable and imperishable He remembers it as well as every appearance that He ever manifested.

Commentary by Sri Madhvacharya of Brahma Sampradaya:

Sri Madhvacharya did not comment on this sloka.

Commentary by Sri Keshava Kashmiri of Kumara Sampradaya:

Although Arjuna had experienced many wonderful and divine lila’s or pastimes with Lord Krishna still he could understand that it would be difficult for others to fathom the reality of His teaching the demigod of the sun Visvavan 120 million years previous. So Arjuna posed this question for Lord Krishna who is isvara or the Ultimate Controller and Supreme Ruler of all creation, time and action. He alone is the ultimate reality and highest destination who incarnated in the family of Vasudeva in order to remove the speculations of those whose minds were made impure by tendency to sinful activities as well as to eradicate the demoniac elements present who were polluting the Earth. The question was asked so Lord Krishna could confirm the truth Himself regarding His transcendental appearance and supra- mundane phenomenal exploits that the miscreants and non-believers refuse to except as being possible for the Supreme Lord. By answering this question all doubts would be cleared up about Lord Krishna’s supreme position.

Commentary by Sri Adi Shankaracharya of Advaita Sampradaya:

4.5 O Arjuna, bahuni, many; janmani, lives; me, of Mine; vyatitani, have passed; tava ca, and so have yours. Aham, I; veda know; tani, them; sarvani, all; (but) tvam, you; va vetta, know not, due to your power of understanding being obstructed by righteousness, unrighteousness, etc. However, parantapa, O scorcher of foes; aham, I know, possessing as I do unobstructed power of knowledge, because by nature I am enternal, pure, enlightened and free. ‘In that case, how, in spite of the absence of righteousness and unrighteousness, can there be any birth for You who are the eternal God?’ That is beng answered:

Commentary by Sri Abhinavagupta of Kaula Tantra Sampradaya:

4.5-9 Bahuni etc. upto Arjuna. Indeed the Bhagavat is Himself devoid of all bodily connections on account of His having the group of the ‘six attributes’ in toto. Yet, out of His nature of stabilising [the universe], and out of compassion, He sends forth (or creates) that is which the Self is secondary. The meaning is this : He takes hold of a body, in which the Self, with the group of ‘six qualities’ in full, remains secondary because of Its role as a helper of the body. On account of this, His birth is divine. For, it has been created not by the results of actions, but by His own Trick-of-Illusion, by the highest knowledge of Yoga, and by the energy of Freedom of His own. His action too is divine, as it is incabable of yielding fruits [for Him]. Whosoever knows this truth in this manner i.e., realises in his own Self also in this manner, he necessarily understands the Bhagavat Vasudeva beng.

Sanskrit Shloka Without Transliteration Marks:

sri-bhagavan uvaca
bahuni me vyatitani
janmani tava carjuna
tany aham veda sarvani
na tvam vettha parantapa

Sanskrit to English Word for Word Meanings:

sri-bhagavan uvaca — the Personality of Godhead said; bahuni — many; me — of Mine; vyatitani — have passed; janmani — births; tava — of yours; ca — and also; arjuna — O Arjuna; tani — those; aham — I; veda — do know; sarvan?i — all; na — not; tvam — you; vettha — know; parantapa — O subduer of the enemy.