Bhagavad Gita 4:7-8

Bhagavad Gita four, verses seven and eight, contains Krishna's own statement of the avatar doctrine, among the most quoted verses in the entire text. Krishna declares that whenever righteousness, dharma, declines and unrighteousness rises, he sends himself forth, taking birth age after age for the protection of the good, the destruction of evildoers, and the establishment of dharma. The verses present divine descent not as a single unrepeatable event but as a recurring pattern triggered by moral crisis, occurring whenever the balance between dharma and its opposite tips too far, rather than on any fixed schedule. Spoken within the Gita's own frame as Krishna's direct address to Arjuna on the battlefield, the passage also functions as a claim about the speaker's own nature, since Krishna is explaining why he, as the supreme deity, can appear within history as a particular human figure without ceasing to be what he fundamentally is, a question the following verses of the same chapter continue to address in greater philosophical detail than these two alone provide, since the Gita goes on to describe Krishna's births as unlike ordinary birth precisely because his own nature remains unchanged and undiminished by each descent.

The avatar doctrine stated in these two verses became one of the most consequential passages in the Gita for later Vaishnava theology, since it supplied scriptural grounding for identifying particular historical and legendary figures as descents of Vishnu. Tradition came to organize ten principal avatars, the dashavatara, into a list that includes Rama and Krishna himself among figures drawn from older mythology, reading each as an instance of the same pattern the Gita states here in the abstract, appearance in a time of crisis for the restoration of dharma. Because the verses ground avatar doctrine in recurring moral crisis rather than in a single cosmic event, later Vaishnava thinkers used the passage to explain why new avatars remain possible in principle even after the classical list was fixed, since the underlying condition the verses name, dharma's decline, is not confined to any one age. The passage is also frequently read alongside the Gita's wider argument that Krishna's teaching applies beyond any single historical moment, since a doctrine of recurring descent implies a god who remains active in each subsequent age rather than one whose involvement with the world ended with a single incarnation many centuries in the past.