Śatapatha Brāhmaṇa ("of a hundred paths") 3.7.3.6

3.7.3.6

tatho evaiṣa etat | uparudhyaiva paśumagnim mathitvāgnāvagniṃ juhoti sa vedaiṣa vai kila haviṣo yāma eṣā pratiṣṭhāgnau vai kila havirjuhvatīti tato 'bhyavaiti tato rātamanā ālambhāya bhavati tasmādupākṛtya paśumagnim mathitvā niyunakti

And in like manner does he now offer fire into the fire, after securing the animal and churning the fire. It (the animal) knows that this truly is the manner of sacrificial food, this its resort; that it is truly in fire that sacrificial food is offered; and accordingly it resigns itself and becomes favourably disposed to the slaughtering. Therefore having driven up the victim and churned the fire, he binds it (to the stake).