Śatapatha Brāhmaṇa ("of a hundred paths") 11.2.7.4

11.2.7.4

ardhamāsā haviṣpātrāṇi sa yo ha vā ardhamāsā haviṣpātrāṇīti vedānte haivāsyārdhamāsānāmiṣṭam bhavatyatho yatkiṃ cārdhamāseṣu kriyate sarvaṃ haivāsya tadāptamavaruddhamabhijitam bhavati

The oblation-vessels are the half-months; and, verily, sacrifice is offered at the end of the half-months of him whoso knows that the oblation-vessels are the half-months; and all that is done in the half-months comes to be gained, secured, and won for him.