Aśauca-vidhi (Rules of Impurity) within Śrāddha-kalpa — Chapter on Testing/Selecting Brahmanas and Honoring the Atithi
यस्मिन्दोषाः प्रदृश्येरम्स हि कार्येषु वर्जितः / जानीयाद्वापि संवासाद्वर्जयेत्तं प्रयत्नतः
yasmindoṣāḥ pradṛśyeramsa hi kāryeṣu varjitaḥ / jānīyādvāpi saṃvāsādvarjayettaṃ prayatnataḥ
He in whom faults are seen is to be excluded from sacred duties. Even through close association one may know him; therefore avoid him with earnest effort.