Shatapatha Brahmana 10.4.1.10

10.4.1.10

etaddha sma vai tadvidvāñcyāparṇaḥ sāyakāyana āha yadvai ma idaṃ karma samāpsyata mamaiva prajā salvānāṃ rājāno'bhaviṣyanmama brāhmaṇā mama vaiśyā yattu ma etāvatkarmaṇaḥ samāpi tena ma ubhayathā salvānprajātirekṣyata iti sa eṣa eva śrīreṣa yaśa eṣo'nnādaḥ

And, indeed, Syâparna Sâyakâyana, knowing this, once said, 'If this my sacrificial performance were complete, my own race would become the kings (nobles), Brâhmanas, and peasants of the Salvas; but even by that much of my work which has been completed my race will surpass the Salvas in both ways;'--for this (Agni, the fire-altar), indeed, is (social) eminence and fame, and an eater of food.