Bhagavad Gita · Raja Vidya Raja Guhya YogaChapter 9, Shloka 30 (9.30)

Shankaracharya. Su-durācāraḥ suṣṭhu durācāraḥ atīva kutsitācāro'pi — even one whose conduct is utterly blameworthy; sādhur eva samyag-vṛtta eva saḥ mantavyaḥ … samyak yathāvat vyavasito hi saḥ yasmāt sādhu-niścayaḥ saḥ — regard him as one of right conduct, because his resolve is right; further on (9.31): utsṛjya ca bāhyāṃ durācāratām antaḥ samyag-vyavasāya-sāmarthyāt — by the power of the right resolve within, the bad conduct outside falls away.

Acharya Ramanuja — "foremost among Vaishnavas". tatra tatra jāti-viśeṣe jātānāṃ yaḥ samācāra upādeyaḥ pariharaṇīyaḥ ca tasmād ativṛttaḥ api — even one who has broken the rules of conduct of his own tradition; sādhuḥ eva saḥ vaiṣṇavāgresara eva mantavyaḥ bahumantavyaḥ — is a saint, to be regarded as foremost among Vaishnavas, worthy of great respect; his resolve: bhagavān … asmat-svāmī mama guruḥ mama suhṛd mama paraṃ bhogyam — "the Lord is my master, my guru, my friend, my supreme beloved"; tasya ācāra-vyatikramaḥ svalpa-vaikalyam iti na tāvatā anādaraṇīyaḥ — his lapse in conduct is a small shortcoming, and he is not to be disrespected for it.