YV 3.7f

There can be no Sattra where there is no Chandoma; in that there are Chandomas, there is the sacrifice. The gods they win by the Prsthas, the cattle by the Chandomas. The Prsthas are force and strength, the Chandomas cattle; verily in force and strength, and in cattle, they find support. (The rite is) of seventeen nights; Prajapati is seventeenfold; (verily it serves) to obtain Prajapati. There are Atiratras on either side, for securing food. The Viraj dividing itself stayed among the gods with the holy power (Brahman), among the Asuras with food. The gods desired, 'May we acquire both the holy power (Brahman) and food! They saw (the rite of) these twenty nights. Then indeed they acquired both the holy power (Brahman) and food, and became resplendent and eaters of food. Those, who knowing thus perform (the rite of) these nights, acquire both the holy power (Brahman) and food [1], and become resplendent and eaters of food. They (make up) two Virajs; verily separately in them they find support. Man is twentyfold, ten fingers and ten toes; verily obtaining the greatness of man they cease (the rite). There are Tryahas consisting of Jyotis, Go, and Ayus. The Jyotis is this (earth), the Go the atmosphere, the Ayus yonder (sky); verily they mount upon these worlds. The Tryahas go in order; verily in order they mount the world of heaven [2]. If the Prsthas were on one side there would be a lack of balance; the Prsthas are in the middle, for balance. The Prsthas are force and strength; verily they place force and strength in the middle. They proceed with the Brhat and the Rathantara (Samans). The Rathantara is this (earth), the Brhat yonder (sky); verily with them do they proceed, verily also in them they find support. These indeed are the quick paths of the sacrifice; verily by them do they proceed to the world of heaven. They mount the world of heaven turning away (from earth), who perform the Prsthas in succession.