Shatapatha Brahmana 1.1.1.13

1.1.1.13

sa praṇayati | kastvā yunakti sa tvā yunakti kasmai tvā yunakti tasmai tvā yunaktītyetābhiraniruktābhirvyāhṛtibhiranirukto vai prajāpatih prajāpatiryajñastatprajāpatimevaitadyajñaṃ yunakti

He brings it forward with those mysterious words (Vâg. S. I, 6): 'Who (or Pragâpati) joins (or yokes) thee (to this fire)? He joins thee. For what (or, for Pragâpati) does he join thee? For that (or him) he joins thee!' For Pragâpati is undefined (mysterious); Pragâpati is the sacrifice: hence he thereby yokes (gets ready for the performance) Pragâpati, this sacrifice.