Brihadaranyaka-Upanishad: Fifth Adhyâya, Twelfth Brahmana

1. Some say that food is Brahman, but this is not so, for food decays without life (prâna). Others say that life (prâna) is Brahman, but this is not so, for life dries up without food. Then these two deities (food and life), when they have become one, reach that highest state (i.e. are Brahman). Thereupon Pratrida said to his father: “Shall I be able to do any good to one who knows this, or shall I be able to do him any harm?” The father said to him, beckoning with his hand: “Not so, O Pratrida; for who could reach the highest state, if he has only got to the oneness of these two?” He then said to him: “Vi; verily, food is Vi, for all these beings rest (vishtani) on food.” He then said: “Ram; verily, life is Ram, for all these beings delight (ramante) in life. All beings rest on him, all beings delight in him who knows this.”