Śatapatha Brāhmaṇa ("of a hundred paths") 1.6.3.39

1.6.3.39

uttarārdhapūrvārdhe haike | āgneyamājyabhāgaṃ juhvati dakṣiṇārdhapūrvārdhe saumyamājyabhāgametatpurastāccakṣuṣī dadhma iti vadantastadu tadāvijñānyamiva havīṃṣi ha vā ātmā yajñasya sa yadeva purastāddhaviṣāṃ juhoti tatpurastāccakṣuṣī dadhāti yatro eva samiddhatam manyeta tadāhutīrjuhuyātsamiddhahomena hyeva samṛddhā āhutayaḥ

Some people offer Agni's butter-portion in the north-eastern part (of the fire), and Soma's butter-portion in the south-eastern part, thinking, 'Thereby we place the eyes in the front (of the head).' This, however, is rather unintelligible; for the several dishes of sacrificial food (havis) represent the body of the sacrifice; when therefore he offers in front of (or before) the havis, he thereby places the eyes in the front. Let him rather make the offerings (in that part of the fire) where he thinks the fiercest blaze is; for only by being offered in blazing (fire) are oblations successful.