Aitareyabrahmana 3.41

3.41

So much for [what comes] before; now for [what comes] after.
There are fifteen stotras and fifteen śastras of the ukthya [sacrifice]; that is a month.
The year is arranged month by month;
the year is Agni Vaiśvānara; Agni is the agniṣṭoma.
Following the year, the ukthya enters into the agniṣṭoma.
Following the ukthya entering [into it], the vājapeya enters, for it is an ukthya.
There are twelve rounds of the night, all of fifteen [verses]; each pair of them, adding up, becomes thirty.
The ṣoḍaśin chant is of twenty-one [verses], the twilight stotra of nine: that is thirty, that is a month.
Thirty are the nights of a month.
The year is arranged month by month; the year is Agni Vaiśvānara; Agni is the agniṣṭoma.
Following the year, the atirātra enters into the agniṣṭoma.
Following the atirātra entering [into it], the aptoryāma enters, for it is an atirātra.
Thus whatever sacrificial rites there are before and whatever there are after,
they all enter into the agniṣṭoma.
When it is fully praised, there are a hundred and ninety stotriya verses.
As for that ninety, they are ten ninefold [stomas];
then as for that ninety, they are ten; then as for the ten,
one stotriya verse among them rises up; a ninefold [stoma] is left over:
that twenty-first one up there burns, placed upon [them]. He is indeed the viṣuvant of the stomas.
Ten ninefold [stomas] are on this near side of him, ten on the far side;
in the middle, this twenty-first one burns, placed upon [them] on both sides.
Then, that stotriya verse which rises up is mounted upon him;
that is the sacrificer, that is divine dominion, might, and strength.
He attains divine dominion, might, and strength;
he attains union, identity of form, and the same world with him who knows thus.