Kauṣītaki (Śāṅkhāyana) Brāhmaṇa 30.5.3

30.5.3

vayam pūrve svargam lokam eṣyāma ity ādityāḥ / (soma: hotraka śastrāṇi(tṛtīya savanam))
vayam ity aṅgirasaḥ /

xxx. 6. (The verses) of the Ādityas and Aṅgirases he recites next. The Ādityas and the Aṅgirases were at variance, 'We shall go first to the world

of heaven' (said) the Āditya; 'we' the Aṅgirases. The Aṅgirases sent to the Ādityas (saying) 'Ours is the pressing day to-morrow; do ye cause us to sacrifice.' Agni was their envoy; the Ādityas said 'Ours is the pressing day to-day; and thou art the Hotṛ for us here, Bṛhaspati the Brahman, Ayāsya the Udgātṛ, Ghora Āṅgirasa the Ādhvaryu.' Them they rejected; him they desired to please with these (verses); thus they repeat these (verses). They brought a white horse as sacrificial fee, that one which here gives heat; therefore the Ādityas went to heaven; he goes to heaven who knows thus.