Śatapatha Brāhmaṇa ("of a hundred paths") 1.7.4.21

1.7.4.21

sa yadi purā mānuṣīṃ vācaṃ vyāharet | tatro vaiṣṇavīmṛcaṃvā yajurvā japedyajño vai viṣṇustadyajñam punarārabhate tasyo haiṣā prāyaścittiḥ

When he (the Adhvaryu) says, 'Brahman, shall I step forward?' the Brahman mutters thus (Vâg. S. II, 12), 'This thy sacrifice, O divine Savitri, they have announced...,'--thereby he has recourse to Savitri for his impulsion (prasava), for he is the impeller (prasavitri) of the gods;--'to Brihaspati, the Brahman,'--for Brihaspati, assuredly, is the Brahman of the gods: hence he announces that (sacrifice) to him who is the Brahman of the gods; and accordingly he says, 'to Brihaspati, the Brahman.'--'Therefore prosper the sacrifice, prosper the lord of sacrifice, prosper me!' In this there is nothing that requires explanation.