Hurtful actions and reprisals are different but closely related. Actions once done are finished with, there’s no need to answer with revenge and hostility. This is called “action” (kamma). “Reprisal” (vera) means to continue that action further with thoughts of “you did it to me so I’m going to get you back.” There’s no end to this. It brings about the continual seeking of revenge, and so hatred is never abandoned. As long as we behave like this the chain remains unbroken, there’s no end to it. No matter where we go, the feuding continues. ~Ajahn Chah