You have heard that it has been said, An eye for an eye, and a tooth for a tooth:
All Commentaries on Matthew 5:38 Go To Matthew 5
Augustine of Hippo
AD 430
It is the lesser righteousness of the Pharisees not to go beyond measure in revenge, that no one should give back more than he has received: and this is a great step. For it is not easy to find any one who, when he has received a blow, wishes merely to return the blow; and who, on hearing one word from a man who reviles him, is content to return only one, and that just an equivalent; but he avenges it more immoderately, either under the disturbing influence of anger, or because he thinks it just, that he who first inflicted injury should suffer more severe injury than he suffered who had not inflicted injury. Such a spirit was in great measure restrained by the law, where it was written, An eye for an eye, and a tooth for a tooth; by which expressions a certain measure is intended, so that the vengeance should not exceed the injury. And this is the beginning of peace: but perfect peace is to have no wish at all for such vengeance.