The Bhagavadgita -S. Radhakrishnan
4. Ultimate Reality
The three functions cannot be torn apart. Brahma, Visnu and Siva are fundamentally one though conceived in a threefold manner. The Gita is interested in the process of redeeming the world. So the aspect of Visnu is emphasized. Krsna represents the Visnu aspect of the Supreme. Visnu is a familiar deity in the Rg. Veda. He is the great pervader, from vis, to pervade. He is the internal controller who pervades the whole universe. He gathers to Himself in an ever increasing measure the position and dignity of the Eternal Supreme. Taittiriya Aranyaka says : "To Narayana we bring worship ; to Vasudeva our meditations and in this may Visnu assist us. "
Krsna,  the teacher of the Gita, becomes identified with Visnu, the ancient Lord of the Sun, and Narayana, an ancient God of cosmic character and the goal or resting place of gods and men.
References and Context
- Amara states, vyapake paramevare. It is traced also from vis, to enter. Taittnriya Up. says : "Having created that world, he after-wards entered into it." See also Padma Purana. Visnu as the Lord entered into prakrti. sa eva bhagavan visnuh prakrtyam avivesaha.
- X, I, 6. naraya u ya vidmahe vasudevaya dhimahi tan no visnuh pracodayat Narayana says : "Being like the Sun, I cover the whole world with rays, and I am also the sustainer of all beings and am hence called Vasudeva." M.B., XII, 341, 41.
- karsati sarvarm krsnah. He who attracts all or arouses devotion in all is krsna. Vedantaratnamanjusa (p. 52) says that Krsna is so called because he removes the sins of his devotees, papam karsayati, nirmulayati. Krsna is derived from krs, to scrape, because he scrapes or draws away all sins and other sources of evil from his devotees. krsater vslekhanarthasya rupam bhaktajanapapcidtidosakarsanat krsnah. Q.B.G., VI, 34