Jesus calls us to imitate the Father's own style of forgiving. St. Paul says: “It is precisely in this that God proves his love for us: that while we were still sinners, Christ died for us” (Rom 5). Jesus showed his Father's mind and heart in the Sermon on the Mount: “Love your enemy and do good; lend without expecting repayment. Then will your recompense be great. You will rightly be called children of the Most High, since he himself is good to the ungrateful and the wicked” (Lk 6). Members of the family of God behave like the Father.
We can deal with injuries and resentments by repressing our feelings; they will fester inside. We can take revenge, obviously or in very sly ways; that will guarantee further injuries and more resentment all around. We can see ourselves as martyrs; that will inflate our egos. Finally, we can let go because that is what the Father and Jesus do. Only by letting go will we find peace and become peacemakers.
Lord, once I behaved as an enemy. Your love found me and you forgave me from your heart. You have shown me how to forgive others as you have forgiven me.