Śatapatha Brāhmaṇa ("of a hundred paths") 14.2.2.13

14.2.2.13

athopayamanyā mahāvīra ānayati svāhā gharmāyetyeṣa vai gharmo ya eṣa tapatyeṣa u pravargyastadetamevaitatprīṇāti tasmādāha svāhā gharmāyetyavaraṃ svāhākāraṃ karoti parāṃ devatāmasāveva bandhuḥ

He then pours (the spilt milk and ghee) from the tray into the Mahâvîra (pot) with, 'Hail to the Gharma!'--the Gharma (hot draught) is he who shines yonder, and the Pravargya also is that (sun): thus it is him he thereby pleases, and therefore he says, 'Hail to the Gharma!'--the call of 'hail!' he places first, and the deity last: the significance of this is the same as before.