Śatapatha Brāhmaṇa ("of a hundred paths") 7.1.2.12

7.1.2.12

tasya gārhapatya evāyaṃ lokaḥ | atha yo gārhapatye 'gnirya evāyamasmiṃloke 'gniḥ so 'sya so 'tha yadantarāhavanīyaṃ ca gārhapatyaṃ ca tadantarikṣamatha ya āgnīdhrīye 'gnirya evāyamantarikṣe vāyuḥ so 'sya sa āhavanīya eva dyauratha ya āhavanīye 'gnistau sūryācandramasau so 'syaiṣa ātmaiva

This (terrestrial) world in truth is his (Pragâpati's) Gârhapatya (hearth); and what fire there is in this world that to him is the fire on the Gârhapatya. And what space there is between the Âhavanîya and the Gârhapatya, that is the air; and that wind in the air is for him the fire on the Âgnîdhrîya. The sky is his Âhavanîya (hearth), and those two, the sun and the moon, are the fire on the Âhavanîya. This then is indeed his own self.