Manava Dharmashastra 2.6

2.6

vedo 'khilo dharmamūlaṃ smṛtiśīle ca tadvidām
ācāraś caiva sādhūnām ātmanas tuṣṭir eva ca //

The whole Veda is the (first) source of the sacred law, next the tradition and the virtuous conduct of those who know the (Veda further), also the customs of holy men, and (finally) self-satisfaction.