Śatapatha Brāhmaṇa ("of a hundred paths") 8.6.3.19

8.6.3.19

tam patnībhiranugacema devāḥ | putrairbhrātṛbhiruta vā hiraṇyairityetenainaṃ sarveṇānugacemetyetannākaṃ gṛbhṇānāḥ sukṛtasya loka iti svargo vai loko nākaḥ svargaṃ lokaṃ gṛhṇānāḥ sukṛtasya loka ityetattṛtīye pṛṣṭhe adhi rocane diva ityetaddha tṛtīyam pṛṣṭhaṃ rocanaṃ divo yatraiṣa etattapati

[The second brick, with, Vâg. S. XV, 50], 'With our wives let us follow him, O gods! with our sons and brothers, or our golden treasures;'--that is, 'let us follow him with our all;'--'gaining the firmament in the world of righteousness;'--the firmament, doubtless, is the heavenly world: thus, 'gaining the heavenly world in the world of righteousness;'--'above the third luminous back of the sky,'--for this, indeed, is the third luminous back of the sky where this (Agni) now burns.