Śatapatha Brāhmaṇa ("of a hundred paths") 5.4.2.5

5.4.2.5

so 'nuvimṛṣṭe | pra parvatasya vṛṣabhasya pṛṣṭhāditi yathāyam parvato 'tiṣṭhāvā yatharṣabhaḥ paśūnatiṣṭhāvaivaṃ vā eṣa idaṃ sarvamatitiṣṭhatyarvāgevāsmādidaṃ sarvam bhavati yo rājasūyena yajate tasmādāha pra parvatasya vṛṣabhasya pṛṣṭhānnāvaścaranti svasica iyānāḥ tā āvavṛtrannadharāgudaktā ahim budhnyamanu rīyamāṇā iti

He rubs it over himself, with (Vâg. S. X, 19), Forth from the back of the mountain, of the bull,'--even as the mountain stands out here, even as the bull stands out beyond the cattle, so does he who performs the Râgasûya stand out beyond everything here, and everything here is below him: therefore he says, 'Forth from the back of the mountain, of the bull,'--'The ships keep moving, the self-pouring; they, the upwards bent, have turned back downwards, flowing after the dragon of the deep.'