Śatapatha Brāhmaṇa ("of a hundred paths") 1.9.1.2

1.9.1.2

yajñaṃ vā eṣa janayati | yo yajata etena hyuktā ṛtvijastanvate taṃ janayantyathāśiṣamāśāste tāmasmai yajña āśiṣaṃ saṃnamayati yāmāśiṣamāśāste yo mājījanateti tasmādvā upariṣṭādyajñasyāśiṣamāśāste

He who sacrifices, assuredly, is the producer of the sacrifice, since it is by his order that, the priests spread it, that they produce it. He (the Hotri) now invokes a blessing; and that blessing invoked by him, the sacrifice, on its part, realises for this (sacrificer), knowing as it does that he has produced it. For this reason he invokes a blessing after the sacrifice.