Psalms 37: 8 “Let go of anger, and put off anger; don't get excited in any way or do wrong. ”

Both the feeling of anger and anger are fruits of the flesh, and it is impossible that any human being has not experienced it. But these are not good for which the Lord advises us to leave and discard them.
An angry person does not think clearly and surely he will want to do justice by his own hands, trying to appease that anger by taking revenge.
For this reason God tells us not to get excited to do evil. He who thinks of revenge only wants to do evil, he wants the other person to feel the same way that he made him feel.
God grant do not pay badly for evil, but the nature of man will always make us fail, because when something bad happens, the flesh reacts negatively and activates the sense of revenge. God will always be there to tell us what is right and what is wrong, he is there to instruct us in a good walk and to exhort us when he knows that what we are doing is not right.
So let's focus on doing good and God will reward us for our good works, remember that God says in his word that of him is revenge, so let's leave everything in God's hands and everything will be fine.