Theophylact of Ohrid
Catena Aurea · Lukasevangelium 17
Lk 17, Verses 3–4English original
Take heed to yourselves: If thy brother trespass against thee, rebuke him; and if he repent, forgive him. And if he trespass against thee seven times in a day, and seven times in a day turn again to thee, saying, I repent; thou shalt forgive him.
As if He says, Offences must needs come; but it does not follow that you must perish, if only you be on your guard: as it need not that the sheep should perish when the wolf comes, if the shepherd is watching. And since there are great varieties of offenders, (for some are incurable, some are curable,) He therefore adds, If thy brother trespass against thee, rebuke him.