Jaiminīya (Talavakāra) Brāhmaṇa 2-2.3

2-2.3

parihṛtāni duhre
sa yathā spandanāṃ rajjubhirvyapatatya duhyurevametānyupariṣṭādvyūḍhe daśarātre gāyatryā
parihṛtāni duhre
sa yathā upasṛjedevaṃ tadyadgāyatramukhastryaho yathābhidadhyādevaṃ tadyadgāyatramadhyo
yathāpahṛtya duhyādevaṃ tadyadgāyatrottamaḥ
tasmādupariṣṭādevopetyānīti
tadu hovāca śāṭyāyaniryo vā eṣa candramā eṣa vāva saṃvatsara eṣa
prajāpatireṣa māsa iti
etāvānvāvaiṣa yāvānmāsaḥ
etaṃ vāvaiṣa āptvā punaḥ palyayate
sa pañcadaśa rātrīrūrdhva eti pañcadaśārvāṅ
yā āpūryate tā ūrdhva etyatha yā apochestā arvāṅ
sa āpūryamāṇo'muṃ lokaṃ gacchati
so'munā lokena saṃspṛśyānnaṃ bhavati
sa yadasya tatra svadyaṃ tatsvada ityapochannimaṃ lokaṃ āgacchati
sa imā apa oṣadhīḥ praviśati
sa imā apa oṣadhīḥ praviśyāsvapsvoṣadhīṣvātmānaṃ nyudyāpūryamāṇo'muṃ lokaṃ
gacchati

Just as they would milk a restive cow having bound her with ropes on all sides, so these are milked after the arranged ten-day rite, surrounded by the Gāyatrī. As one would let loose [the calf], so is that three-day period with the Gāyatrī at the beginning; as one would bind [her legs], so is that with the Gāyatrī in the middle; as one would milk after taking [the milk-pail], so is that with the Gāyatrī at the end. Therefore they should be undertaken only at the end.' But Śāṭyāyani said: 'The moon here is indeed the year, he is Prajāpati, he is the month. He is of such extent as is the month. Having attained this [measure], he rolls back again. He goes upward for fifteen nights, downward for fifteen. The nights during which he fills up, he goes upward; then the nights during which he wanes, downward. Filling up, he goes to that world. Coming into contact with that world, he becomes food. Tasting what is savored for him there, waning with: "Taste!", he comes to this world. He enters these waters and plants. Having entered these waters and plants, having submerged himself in the waters and plants, filling up, he goes to that world.