Here is a promise, If you forgive, your heavenly Father will also forgive. We must forgive, as we hope to be forgiven. Those who desire to find mercy with God, must show mercy to their brethren. Christ came into the world as the great Peace-maker, not only to reconcile us to God, but one to another.
Matthew 6:14-15 (New King James Version)
14 “For if you forgive men their trespasses, your heavenly Father will also forgive you. 15 But if you do not forgive men their trespasses, neither will your Father forgive your trespasses.