Cyril of Alexandria
Catena Aurea · Lukasevangelium 17
Then said he unto the disciples, It is impossible but that offences will come: but woe unto him, through whom they come! It were better for him that a millstone were hanged about his neck, and he cast into the sea, than that he should offend one of these little ones.
Now there are two kinds of offences, of which the one resist the glory of God, but the other serve only to cause a stumbling-block to the brethren. For the inventions of heresies, and every word that is spoken against the truth, are obstructions to the glory of God. Such offences however do not seem to be mentioned here, but rather those which occur between friends and brethren, as strifes, slanders, and the like. Therefore He adds afterwards, If thy brother trespass against thee, rebuke him.