For if justice be a virtue, it must be free from the imputation of crime, and not return evil for evil. For what kind of virtue is it for you to do yourself what you punish in another? This is merely to propagate iniquity, not to punish it; and the character of the person whom you injure, whether he be just or unjust, makes no difference, for you ought not to have done evil.

Ambrose of Milan (339-397) Roman theologian, statesman, Christian prelate, saint, Doctor of the Church [Aurelius Ambrosius]

Letter to the Church of Vercellae, para. 83
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