LEV718 Do not take vengeance against your fellow Jew. Each of us must realize that whatever happens to him is only because Hashem decrees it. Therefore, if someone causes us pain or suffering of any sort, he must realize that he is not the root cause. Rather, the root cause is our sins, and Hashem decreed that the pain or suffering befall us. If this fact is clear to us, we will not take vengeance on those who harm us or cause us suffering. In addition, a great benefit derives to us from this mitzvah, for it quells hatred before it has a chance to grow, so it prevents outbreaks of strife and quarrelling. When people do not take vengeance and do their best to live in peace with one another, Hashem will bless them and grant them peace.