“This is how my heavenly Father will treat each of you unless you forgive your brother from your heart” (Matt. 18:35). It is either forgive or perish. God has forgiven the infinite debt of your sin. Now you must forgive anyone who sins against you. Otherwise, you prove that you have never received forgiveness in the first place, that you are still in God's debt and therefore liable to the perfect severity of His justice.
Philip Graham Ryken