菩薩戒本疏 1.55

1.55

If a disciple of the Buddha himself speaks of the faults of home-leaving or lay bodhisattvas, bhikṣus, or bhikṣuṇīs, or teaches others to speak of their faults—the causes of faults, the conditions of faults, the methods of faults, the karma of faults—yet a bodhisattva, upon hearing non-Buddhists of evil intent or evil persons of the two vehicles speak of what is contrary to Dharma and contrary to Vinaya within the Buddha's teaching, should always give rise to a mind of compassion and convert these evil persons, causing them to generate wholesome faith in the Mahāyāna; but if the bodhisattva instead speaks himself of faults within the Buddha's teaching, this is a bodhisattva parājika offense.