Aitareyabrahmana 3.43

3.43

Now this [rite] is just Agni, which is the agniṣṭoma; because they praised him, therefore it is agnistoma ['Agni's praise'].
Being agnistoma, they cryptically call it agniṣṭoma,
for the gods are fond of the cryptic, as it were.
Because the fourfold gods praised him with four stomas, therefore it is catustoma ['four-stoma'].
Being catustoma, they cryptically call it catuṣṭoma,
for the gods are fond of the cryptic, as it were.
Then, because they praised him being upward, having become light, therefore it is jyotistoma ['light-stoma'].
Being jyotistoma, they cryptically call it jyotiṣṭoma,
for the gods are fond of the cryptic, as it were.
Now this is a sacrificial performance having neither predecessor nor successor;
just as a chariot wheel is endless, so is the agniṣṭoma.
Just as its opening is, so is its conclusion.
Regarding that, this sacrificial verse is sung:
'What is its beginning, that is its end;
and what is its end, that is its beginning;
like the crawling of a Śākala snake,
they do not distinguish which is on the other side,'
so [it says],
so that its conclusion may be just like its opening.
On this they say: 'Since the trivṛt is the opening and the ekaviṃśa is the conclusion, by what are the two equal?'
That which is the ekaviṃśa is indeed the trivṛt;
moreover, one should say: 'Because both are composed of triplets of verses'—by that.