When His disciples asked Him how to pray, Jesus taught them the Our Father. In it we pray: “Thy Kingdom come, thy will be done on earth as it is in heaven.” We pray that like Jesus we might be obedient to the Father, carrying out the will of the Father in our lives. One part of that will is to forgive those who sin against us.
Through the prophet Joel, the Lord tells us that if we return to Him “with fasting, weeping, and mourning” that He will relent in punishment and have pity on His people. God even goes so far as to say that He will restore everything that the locust has eaten (Joel 2:25-32).