"But anger has its own pleasure," you might say. "It feels good to pay back the pain you've suffered." Not at all. It's not honorable to answer injuries with injuries, the way it is honorable to repay kindness with kindness. When someone is kind to you, it's shameful to be outdone in generosity. But when someone hurts you, it's shameful to win at hurting back. Revenge and retaliation sound like righteous words. People use them and think they're justified. But they're barely different from plain wrongdoing. The only difference is the order — who started it. The person who gives back pain for pain has a better excuse for their sin. That's all.
"But anger possesses a certain pleasure of its own, and it is sweet to pay back the pain you have suffered." Not at all; it is not honourable to requite injuries by injuries, in the same way as it is to repay benefits by benefits. In the latter case it is a shame to be conquered; in the former it is a shame to conquer. Revenge and retaliation are words which men use and even think to be righteous, yet they do not greatly differ from wrong-doing, except in the order in which they are done: he who renders pain for pain has more excuse for his sin; that is all.