Śatapatha Brāhmaṇa ("of a hundred paths") 7.4.1.16

7.4.1.16

yadveva puruṣamupadadhāti | prajāpatervisrastādramyā tanūrmadhyata udakrāmattasyāmenamutkāntāyāṃ devā ajahustaṃ yatra devāḥ samaskurvaṃstadasminnetāṃ ramyāṃ tanūm madhyato 'dadhustasyāmasya devā aramanta tadyadasyaitasyāṃ ramyāyāṃ tanvāṃ devā aramanta tasmāddhiramyaṃ hiramyaṃ ha vai taddhiraṇyamityācakṣate paro 'kṣam paro 'kṣakāmā hi devāstathaivāsminnayametāṃ ramyāṃ tanūm madhyato dadhāti tasyāmasya devā ramante prāṇo vā asya sā ramyā tanūḥ prāṇamevāsminnetam madhyato dadhāti

And, again, why he lays down the man. When Pragâpati was relaxed, his pleasing form went out from within; when it had gone out of him, the gods left him. When the gods restored him, they put that pleasing form into him, and the gods were pleased with that (form) of his; and inasmuch as the gods were pleased (ram) with that pleasing (ramya) form of his, it is called 'hiramya;' 'hiramya' being what is mystically called 'hiranya' (gold), for the gods love the mystic. And in like manner does this (Sacrificer) now put that pleasing form into him (Agni), and the gods are pleased with that (form) of his. But that pleasing form of his is the vital air: it is that vital air he thus puts into him.