Jesus taught his disciples to pray the Lord’s Prayer. There Jesus said, “For if you forgive others their trespasses, your heavenly Father will also forgive you, but if you do not forgive others their trespasses, neither will your Father forgive your trespasses” (Matthew 6:14–15). Whoever receives forgiveness, should give forgiveness. The Heidelberg Catechism explains it beautifully:
What is the fifth petition?
And forgive us our debts, as we also have forgiven our debtors. That is: For the sake of Christ’s blood, do not impute to us, wretched sinners, any of our transgressions, nor the evil which still clings to us, as we also find this evidence of your grace in us that we are fully determined wholeheartedly to forgive our neighbour.
1 Have mercy on me, O God, according to your steadfast love; according to your abundant mercy blot out my transgressions.