Jaiminīya (Talavakāra) Brāhmaṇa 2-3.41

Now, there were three ancient fires: the Lord of the Earth (Bhūpati), the Lord of the World (Bhuvanapati), and the Lord of Beings (Bhūtānāṃ Pati). This world is the Lord of the Earth; the intermediate region is the Lord of the World; that world is the Lord of Beings. And this one is prosperity (bhūti). The vaṣaṭ-call cut off their heads. They entered into these three earths. Therefore, if anything of the fire-offering or of the melted butter should spill, he should touch it, saying: 'To the Lord of the Earth, svāhā! To the Lord of the World, svāhā! To the Lord of Beings, svāhā!' It is into these fires that it is offered for him, not spilled. Now, there were three ancient sages: Śūrpaṃyava Mashvānā, Antarvān Kṛṣi, and Saulvāla. They saw the injuries of the sacrifice. They saw these expiations for it: 'May there be welfare for me, and approach for me; long life for me, and increase for me; O sacrifice, conclude auspiciously for me; O sacrifice, conclude well-offered for me; O sacrifice, conclude unharmed for me!' Therefore, having sacrificed with the new- and full-moon sacrifices, or with the four-month seasonal sacrifices, or with the animal sacrifice, or with the soma sacrifice, he should mutter these afterwards. Whatever is deficient in the sacrifice here, that he pacifies by means of this. Breath is up to the Viṣuvant; circulating breath is the Viṣuvant; down-breath is what is above the Viṣuvant. Down-breath indeed brings all this. Therefore, after the Viṣuvant, we undertake the six-day rites in reverse order.

Regarding this, Kratujit Jānaki asked Iyapi Saumāpa: 'Does a mortal live here through out-breath or through in-breath?'

'[Through what] does a mortal live here?'

'Declare that to the assembled Brahmins of the Kurus.'

He said: 'Right here will I answer you.'

He answered him: 'Neither through out-breath nor through in-breath.

While a mortal lives here, circulating breath is the overseer of the animal; it drives it in every direction.'

Man indeed is an animal.

He is an animal that looks upward.

Circulating breath indeed drives him in every direction.

Now, some undertake these six-day rites in forward order after the Viṣuvant.

By that pṛṣṭha six-day period which we perform first, they become distinguished.

And so that it is not monotonous.

Regarding this, Śāṭyāyani said: 'Both of these become ascending—those that are ascending and those that are descending.'

'Through the soma pressings these become ascending, and we attain that desire which is in the turns.'

Regarding this they say: 'Just as there is a whirlpool of waters, so are these two: the Go and the Āyus.'

'To which of the days do these belong?'

'To the preceding or to the following?'

One should reply: 'To both.'

For these two hold together both days, the preceding and the following.