Answer

This leads us to the question of double intention (offering a sacrifice for the sake of Passover and for the sake of a peace-offering, and other such topics). Since the prohibition of revenge is, at its core, a mental prohibition (and the act is only a condition), there is room to argue that this does involve a prohibition. However, if he would have done the act even without the feeling of revenge, then it seems to me that the addition of the feeling of revenge is not considered a motive for the act, and therefore there is no formal prohibition (but there is still a moral prohibition). This reminds me of a similar example. There are halakhic decisors who require that in a transgression committed for the sake of Heaven, one must specifically intend it for the sake of Heaven, and otherwise they forbid it. That always seemed absurd to me. If Jael’s deed was in the category of a transgression for the sake of Heaven, which the Sages praise very highly, then if her intention had not been for the sake of Heaven, should she have left Sisera alive?
——————————————————————————————
Questioner:
If I understood you correctly, you said that it is permitted to do the act, even though it involves a moral problem, because in any case I would have done the act even without motives of revenge? If so, why did you write that there is a moral prohibition? (Maybe you meant that there is only a moral problem, but not an actual prohibition?)
——————————————————————————————
Rabbi:
I meant a moral problem. That is the meaning of “moral prohibition.”