Shatapatha Brahmana 10.4.2.26

10.4.2.26

sa es-u triṣu lokeṣūkhāyām yonau reto bhūtamātmānamasiñcaccandomayaṃ stomamayam prāṇamayaṃ devatāmayaṃ tasyārdhamāse prathama ātmā samaskriyata davīyasi paro davīyasi paraḥ saṃvatsara eva sarvaḥ kṛtsnaḥ samaskriyata

Into these three worlds, (in the form of) the fire-pan, he (Pragâpati) poured, as seed into the womb, his own self made up of the metres, stomas, vital airs, and deities. In the course of a half-moon the first body was made up, in a further (half-moon) the next (body), in a further one the next,--in a year he is made up whole and complete.