[504] Furthermore, Upāli, a bhikkhu (bhikkhu) who is an accuser, wishing to accuse another, should reflect thus: 'Have both Pātimokkhas been well learned by me in detail, well analyzed, fluently mastered, well determined, sutta by sutta and in their details? Is this quality found in me, or not?' If, Upāli, both Pātimokkhas have not been well learned by a bhikkhu in detail, well analyzed, fluently mastered, well determined, sutta by sutta and in their details, then, being asked, 'But where, friend, was this said by the Blessed One?', he cannot answer. There will be those who say to him: 'Come now, venerable, first master the Vinaya.' Thus there will be those who say this to him.
Upāli, a bhikkhu who is an accuser, wishing to accuse another, should reflect upon these five qualities within himself and then accuse the other.
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.