Śatapatha Brāhmaṇa ("of a hundred paths") 3.2.4.22

3.2.4.22

taṃ yathaivādo devāḥ | vyahvayanta gandharvaiḥ sā devānupāvartataivamevaināmetadyajamāno vihvayate sā yajamānamupāvartate tāmudīcīmatyākurvantyudīcī hi manuṣyāṇāṃ dikṣo eva yajamānasya tasmādudīcīmatyākurvanti

And as the gods then wooed her with the Gandharvas, and she turned to the gods, so does the sacrificer now woo her, and she turns to the sacrificer. They lead her (the Soma-cow) northwards round (to the place where the Soma is to be sold); for the north is the quarter of men, and hence it is that of the sacrificer for this reason they lead her northwards round.