Śatapatha Brāhmaṇa ("of a hundred paths") 4.1.2.5

4.1.2.5

taṃ devāḥ pavitreṇāpāvayan | sa medhyaḥ pūto devānāṃ havirabhavattatho evainameṣa etatpavitreṇa pāvayati sa medhyaḥ pūto devānāṃ havirbhavati

The gods purified him by some means of purification (or a strainer, pavitra), and, being cleansed and pure, he became the (sacrificial) food of the gods. And in like manner does he now purify him by means of that strainer, and, being cleansed and pure, he becomes the food of the gods.