We see that the mystery of the divine Incarnation in man, the assumption by the Godhead of the human type and the human nature, is in the view of the Gita only the other side of the eternal mystery of human birth itself which is always in its essence, though not in its phenomenal appearance, even such a miraculous assumption. The eternal and universal self of every human being is God; even his personal self is a part of the Godhead, mamaivāṃśaḥ, — not a fraction or fragment, surely, since we cannot think of God as broken up into little pieces, but a partial conciousness of the one Consciousness, a partial power of the one Power, a partial enjoyment of world-being by the one and universal Delight of being, and therefore in manifestation or, as we say, in Nature a limited and finite being of the one infinite and illimitable Being. The stamp of that limitation is an ignorance by which he forgets, not only the Godhead from which he came forth, but the Godhead which is always within him, there living in the secret heart of his own nature, there burning like a veiled Fire on the inner altar in his own temple-house of human consciousness.
He is ignorant because there is upon the eyes of his soul and all its organs the seal of that Nature, Prakriti, Maya, by which he has been put forth into manifestation out of God’s eternal being; she has minted him like a coin out of the precious metal of the divine substance, but overlaid with a strong coating of the alloy of her phenomenal qualities, stamped with her own stamp and mark of animal humanity, and although the secret sign of the Godhead is there, it is at first indistinguishable and always with difficulty decipherable, not to be really discovered except by that initiation into the mystery of our own being which distinguishes a Godward from an earthward humanity. In the Avatar, the divinely-born Man, the real substance shines through the coating; the mark of the seal is there only for form[...].
Every great man who rises above our average level, raises by that very fact our common humanity; he is a living assurance of our divine possibilities, a promise of the Godhead, a glow of the divine Light and a breath of the divine Power.
It is this truth which lies behind the natural human tendency to the deification of great minds and heroic characters; it comes out clearly enough in the Indian habit of mind which easily sees a partial (aṃśa) Avatar in great saints, teachers, founders, or most significantly in the belief of southern Vaishnavas that some of their saints were incarnations of the symbolic living weapons of Vishnu, — for that is what all great spirits are, living powers and weapons of the Divine in the upward march and battle. This idea is innate and inevitable in any mystic or spirital view of life which does not draw an inexorable line between the being and nature of the Divine and our human being and nature; it is the sense of the divine in humanity.
This doctrine is a hard saying, a difficult thing for the human reason to accept; and for an obvious reason, because of the evident humanity of the Avatar. The Avatar is always a dual phenomenon of divinity and humanity; the divine takes upon himself the human nature with all its outward limitations and makes them the circumstances, means, instruments of the divine consciousness and the divine power, a vessel of the divine birth and the divine works. But so surely it must be, since otherwise the object of the Avatar’s descent is not fulfilled; for that object is precisely to show that the human birth with all its limitations can be made such a means and instrument of the divine birth and divine works, precisely to show that the human type of consciousness can be compatible with the divine essence of consciousness made manifest, can be converted into its vessel, drawn into nearer conformity with it by a change of its mould and heightening of its powers of light and love and strength and purity; and to show also how it can be done. If the Avatar were to act in an entirely supernormal fashion, this object would not be fulfilled. A merely supernormal or miraculous Avatar would be a meaningless absurdity[....] The Avatar does not come as a thaumaturgic magician, but as the divine leader of humanity and the exemplar of a divine humanity. [...] The rationalist who would have cried to Christ, “If thou art the Son of God, come down from the cross,” or points out sagely that the Avatar was not divine because he died and died too by disease, — as a dog dieth, — knows not what he is saying: for he has missed the root of the whole matter. Even, the Avatar of sorrow and suffering must come before there can be the Avatar of divine joy; the human limitation must be assumed in order to show how it can be overcome; and the way and the extent of the overcoming, whether internal only or external also, depends upon the stage of the human advance; it must not be done by a non-human miracle.
-Sri Aurobindo, “The Process of Avatarhood,” from Essays on the Gita
It is indeed curious to note that the permanent, vital, universal effect of Buddhism and Christianity has been the force of their ethical, social and practical ideals and their influence even on the men and the ages which have rejected their religious and spiritual beliefs, forms and disciplines; later Hinduism which rejected Buddha, his sangha and his dharma, bears the ineffaceable imprint of the social and ethical influence of Buddhism and its effect on the ideas and the life of the race, while in modern Europe, Christian only in name, humanitarianism is the translation into the ethical and social sphere and the aspiration to liberty, equality and fraternity the translation into the social and political sphere of the spiritual truths of Christianity, the latter especially being effected by men who aggressively rejected the Christian religion and spiritual discipline and by an age which in its intellectual effort of emancipation tried to get rid of Christianity as a creed. On the other hand the life of Rama and Krishna belongs to the prehistoric past which has come down only in poetry and legend and may even be regarded as myths; but it is quite immaterial whether we regard them as myths or historical facts, because their permanent truth and value lie in their persistence as a spiritual form, presence, influence in the inner consciousness of the race and the life of the humans soul. Avatarhood is a fact of divine life and consciousness which may realise itself in an outward action, but must persist, when that action is over and has done its work, in a spiritual influence; or may realise itself in a spiritual influence and teaching, but must then have its permanent effect, even when the new religion or discipline is exhausted, in the thought, temperament and outward life of mankind.
-Sri Aurobindo, “The Divine Birth and Divine Works,” from Essays on the Gita