Shatapatha Brahmana 5.4.5.18

5.4.5.18

sa yadagniṃ yajati | agninaivaitattejasānusaṃsarpatyatha yatsomaṃ yajati somenaivaitadrājñānusaṃsarpatyatha yadviṣṇuṃ yajati yajño vai viṣṇustadyajñam pratyakṣamāpnoti tam pratyakṣamāptvātmankurute

Now when he offers to Agni, he steals along with Agni, with fiery spirit; and when he offers to Soma, he steals along with Soma, the King; and when he offers to Vishnu,--Vishnu being the sacrifice,--he visibly obtains the sacrifice, and having visibly obtained it, he makes it his own (or, takes it in).