Śatapatha Brāhmaṇa ("of a hundred paths") 1.6.4.19

1.6.4.19

taṃ grasitvodeti | sa na purastānna paścāddadṛśe grasate ha vai dviṣantam bhrātṛvyamayamevāsti nāsya sapatnāḥ santītyāhurya evametadveda

Having swallowed him, he (the sun) rises; and that (other) one is not seen either in the east or in the west. And, verily, he who knows this, swallows his spiteful enemy, and of him they say, 'He alone exists, his enemies exist not.'