"I see. With such a dim view as that, perhaps I can see why you confuse revenge with justice. A good king and queen however, do their best to protect and guide their people, and one of the ways they do that is the creation and enforcement of laws. A proper justice system to protect the weak and dissuade people from doing harm to others. Punishment is known in advance. Or at least a selection of punishments are. For many people knowing if they are caught hurting someone they would, for example, spend a number of years in a dungeon, they might be less likely to hurt someone. But if they know of no such law and they hurt someone and then someone hurts them back... they could feel it is unjustified and then seek their own revenge in an endless cycle of escalation."