Śatapatha Brāhmaṇa ("of a hundred paths") 3.3.4.1

3.3.4.1

nīḍe kṛṣṇājinamāstṛṇāti | adityāstvagasīti so 'sāveva bandhurathainamāsādayatyadityai sada āsīdetīyaṃ vai pṛthivyaditiḥ seyam pratiṣṭhā tadasyāmevainametatpratiṣṭhāyām pratiṣṭhāpayati tasmādāhādityai sada āsīdeti

In the enclosed space (of the cart) he (the Adhvaryu) lays down the black deer-skin, with the text (Vâg. S. IV, 30), 'Thou art Aditi's skin;' its significance is the same (as before). Thereon he places him (Soma), with, 'Seat thee on Aditi's seat!' for Aditi being this (earth), and she being indeed a safe resting-place, he thereby places him on that safe resting-place: therefore he says, 'Seat thee on Aditi's seat!'