Śatapatha Brāhmaṇa ("of a hundred paths") 1.8.3.5

1.8.3.5

yajamāna eva juhūmanu | yo 'smā arātīyati sa upabhṛtamanu prāñcamevaitadyajamānamudūhatyapāñcaṃ tamapohati yo 'smā arātīyatyattaiva juhūmanvādya upabhṛtamanu prāñcamevaitadattāramudūhatyapāñcamādyamapohati

Behind the guhû stands the sacrificer, and behind the upabhrit stands he who means evil to him: hereby, then, he brings the sacrificer forward to the front (or east), and the one who means evil him he drives back (or towards the west). Behind the guhû stands the eater (enjoyer), and behind the upabhrit the one to be eaten (enjoyed): thus he now brings the eater (enjoyer) to the front, and the one to be eaten (enjoyed) he drives back.