Shatapatha Brahmana 9.5.1.11

9.5.1.11

agnau hutvātha bhakṣayati | daivo vā asyaiṣa ātmā mānuṣo 'yaṃ devā u vā agre 'tha manuṣyāstasmādagnau hutvātha bhakṣayati

When he has offered in the fire, he drinks (Soma); for that (fire-altar) is his divine body, and this (Sacrificer's own body) is his human one; and the gods were first, and then men: therefore he drinks (Soma), after offering in the fire.