The urge for revenge is natural in humans , this gospel on revenge is a reminder for us to rise above it. The way of forgiveness is what we believers has been called to do. it shows divine strength, and it is not a sign of weakness as many have seen it to be.
As we understood from Ecclesiastes 7:20 , that part of the bible reminds us everybody on earth is born with sin and is not perfect. Mistakes is what shows that we are humans so we also need forgiveness. Forgive is also good for the both parties involved as we free others from guilt and also free ourselves from the bitterness that comes with hatred and harboring grudges.
Sincere forgiveness is what we should learn as believers, this is because our father in heaven forgives us too. when we do this, we are embracing his love ,peace and compassion which is endless.
It is not easy as humans to forgive. Even when we do, we tend not to forget.
But when we understand that everyone sins differently and we aren't saint, we can actually forgive others for their wrongdoings and let go of the past.