Śatapatha Brāhmaṇa ("of a hundred paths") 3.4.1.25

3.4.1.25

atha sruveṇopahatyājyam | agnimabhijuhotyagnāvagniścarati praviṣṭa ṛṣīṇām putro abhiśastipāvā sa naḥ syonaḥ suyajā yajeha devebhyo havyaṃ sadamaprayucantsvāhetyāhutyai vā etamajījanata tametayāhutyāpraiṣīttasmādevamabhijuhoti

He then takes out some clarified butter with the dipping-spoon, and pours it on the fire, with the text (Vâg. S. V, 4), 'Agni resorteth to Agni, he the son of the seers that shieldeth us from curses: graciously offer thou for us now with good offering, never withholding the oblation from the gods, Hail!' For the purpose of offering they have produced him, and by this offering he has now gratified him: that is why he thus makes offering unto him.