Jaiminīya (Talavakāra) Brāhmaṇa 2-7.237

2-7.237

vicchinna iva ha khalu vā eṣa yajñakraturyaddvirātraḥ
gāyatrīṃ pūrvamahassaṃpadyate triṣṭubhamuttaram
atha kva jagatī cānuṣṭupcetyāhuḥ
gāyatrīṃ caiva pūrvamahassaṃpādayettriṣṭubhaṃ ca jagatīṃ cānuṣṭubhaṃ cottaraṃ chandasāṃ
saṃtatyā avyavacchedāya
uccā te jātamandhasetyandhasvatīrbhavatyandhasvadvai jagatyai rūpaṃ tena jagatyai rūpānna
yanti
vaikhānasaṃ bhavati jāgataṃ sāma
tenaiva jagatyai rūpānna yanti
ye dve sāmanī tayoranyataradbhavati yathobhayāpadī pratitiṣṭhettādṛktat
suvarjyotirbhavati
suvarvai pūrvamaharjyotiruttaramahnoreva santatyā ahnossamārambhāya
hāviṣmatahāviṣkṛte svargye sāmanī svargasya lokasya samaṣṭyai
tadāhuḥ kṣipre sāmanī yadubhe kuryurīśvaro yajamānaṃ purāyuṣaḥ pramathitoranādṛtya hi
tāvimaṃ lokamamumeva lokamabhisaṃpraitāmiti
hāviṣmatamevottarasyāhna uktheṣu brahmasāma kuryuḥ
tathā sarvamāyureti gacchati svargaṃ lokam

Disconnected, as it were, is this sacrificial rite, namely the two-day rite.
The first day conforms to the Triṣṭubh, the latter to the Jagatī.
Then they ask: 'Where are the Jagatī and the Anuṣṭubh?'
He should make the first day conform to the Gāyatrī, and the latter to the Triṣṭubh, the Jagatī, and the Anuṣṭubh, for the continuity of the meters, so that there is no severance.
With the verses 'High born is thy juice...' they are endowed with juice; endowed with juice, indeed, is the form of the Jagatī; thereby they do not depart from the form of the Jagatī.
The Vaikhānasa sāman belongs to the Jagatī;
thereby they do not depart from the form of the Jagatī.
Of the two sāmans, it is one or the other, just as one stands firm with both feet; such is that.
Suvar and Jyotis are used;
Suvar is the first day, Jyotis the latter, for the continuity of the two days, for the joining of the two days.
The Hāviṣmata and Hāviṣkṛta are two heavenly sāmans for the attainment of the heavenly world.
Concerning that, they say: 'The two sāmans are swift; if they were to perform both, it could snatch away the sacrificer before his full span of life, for disregarding this world, the two went straight to yonder world.'
They should make only the Hāviṣmata the Brahma-sāman among the ukthas of the latter day.
Thus he attains the full span of life and goes to the heavenly world.