Manava Dharmashastra 12.109

12.109

dharmeṇādhigato yais tu vedaḥ saparibṛṃhaṇaḥ
te śiṣṭā brāhmaṇā jñeyāḥ śrutipratyakṣahetavaḥ //

Those Brahmanas must be considered as Sishtas who, in accordance with the sacred law, have studied the Veda together with its appendages, and are able to adduce proofs perceptible by the senses from the revealed texts.