Shatapatha Brahmana 10.4.2.27

10.4.2.27

tadyatpariśritamupādhatta tadrātrimupādhatta tadanu pañcadaśa muhūrtānmuhūrtānanu pañcadaśāśītīratha yadyajuṣmatīmupādhatta tadaharupādhatta tadanu pañcadaśa muhūrtānmuhūrtānanu pañcadaśāśītīrevametāṃ trayīṃ vidyāmātmannāvapatātmannakuruta so'traiva sarveṣām bhūtānāmātmābhavaccandomaya stomamayaḥ prāṇamayo devatāmayaḥ sa etanmaya eva bhūtvordhva udakrāmatsa yaḥ sa udakrāmadeṣa sa candramāḥ

Whenever he laid down an enclosing-stone, he laid down a night, and along with that fifteen muhûrtas, and along with the muhûrtas fifteen eighties (of syllables of the sacred texts). And whenever he laid down a brick with a formula (yagushmatî), he laid down a day, and along with that fifteen muhûrtas, and along with the muhûrtas fifteen eighties (of syllables). In this manner he put this threefold lore into his own self, and made it his own; and in this very (performance) he became the body of all existing things, (a body) composed of the metres, stomas, vital airs, and deities; and having become composed of all that, he ascended upwards; and he who thus ascended is that moon yonder.