"...The choice to forgive is not an exoneration of the criminal; it is a choice to end the cycle of revenge and leave the matter of justice in the hands of God.
This perspective on justice helps us understand what is know as the imprecatory psalms- the cursing psalms. These are the angry psalms that plead for God to do justice by inflicting his wrath upon the wicked. What we learn from the imprecatory psalms is that rage against injustice belongs before God. Instead of holding rage against injustice in our heart where it is allowed to fester and corrupt, we place our rage before the throne of God, recognizing that God and God alone is capable of judging the world in righteousness. Anger against deep injustice is unavoidable. That anger can be brought before God in an appropriate way through the imprecatory psalms..."
"...The purpose of the 'furious parts of the Psalms,' as C. S. Lewis called them, has to do with placing our anger concerning violent injustice before God and trusting God to bring about justice. But a word of caution: The imprecatory psalms are how the saints have prayed concerning violent and murderous injustice - from ancient Semitic warlords to Nazis. But is is not how we are to pray concerning our brothers and sisters in Christ with whom we simply cannot get along. How Dietrich Bonhoeffer might pray concerning Hitler is not how we are to pray concerning irritating church members. The prayer of imprecatory rage is a response to the monstrous, not the petty."
(from pages 118-119, italics in the original)If you have not read this book, I cannot praise it highly enough. Get it! Read it!