From a homily delivered decades ago by a now-deceased Texas priest:
The statement, “Yes, I forgive you” can be either a genuine desire to restore a wounded relationship, or it can be used as a power play. We see this a great deal in sick romantic relationships when one person always plays the role of the screw-up and the other partner plays the role of the morally superior martyr. Mercy is based in truly desiring to restore relationship with another human being; it is not a way of condescendingly exerting power over another human being. “Yes, Kobe, I forgive you: now where is my six million dollar ring?”
Forgiveness is rooted in trust. To refuse to forgive in a general sense is to refuse to trust in the providence of God. Therefore, being a forgiving person does not mean merely saying, “I accept your apology” to those who offend us, it also means forgiving the world, our own histories, our own situations… it means forgiving ourselves.
Trust is such a key component of the reality of faith. To lack forgiveness is to lack trust. Therefore, forgiveness is not merely a dimension of our faith; it is an essential component of our faith. Religious scholars call our faith a “salvation faith” because it is a religion based on the forgiveness, grace, and mercy of God. The God revealed to us is forgiving as part of his very nature and the story of his forgiveness is the key theme of our scriptures. Saying that we do not want to forgive is tantamount to saying, “I do not want to be part of the life of God.” Saying that we do not want to forgive is tantamount to saying, “I do not want to be Christian.”
Though not in the written record, when he delivered the homily at a Saturday Vigil Mass, he added, after the phrase "it means forgiving ourselves," the verbal parenthetical ("which can often be the hardest thing we do.").
I sat bolt upright during his presentation. I had the uncomfortable feeling that he was talking directly to me. He may have been. During the Mass, as he sprinkled holy water over the congregation, he hit me directly in the face with a full shot, then paused on his journey to whisper in my ear, "Got you good, didn't I? You're next." I have no idea what he meant by that at the time, but I'm finally beginning to get an idea.
Forgiving yourself doesn't mean forgetting that the wrong you have done was wrong, nor the reality that your penance for past misdeeds may be severe, in this world and the next. It does mean, however, that you're not greater than God, and that if God has revealed that He can forgive anything, then your refusal to accept this revelation is the ultimate assertion of a fatal pride. You're no better or worse than any other man or woman: we're all entitled to forgiveness.
To my understanding, the act of forgiving is the conscious release of your internal desire for vindictiveness and hatred, for revenge. Forgiving another's transgressions doesn't mean that you accept abuse or that you don't punish others who violate man's laws, but you should do so with a sense of humility rather than of avenging wrongs, and with more a sense of pity than hatred for a fallen man blinded by his nature from realizing God's love and acting accordingly. And you'd better have the responsibility for taking such action conferred upon you by the proper earthly authorities. If you take justice into your own hands or do it out of a sense that you, another fallen man, are meeting out justice or because you feel hatred or anger, you're taking God's work upon yourself, and you're damned by your pride and your usurpation.
This is one (of many) aspects of being Christian I find personally difficult. Anger at injustice, hatred of the dishonest and the evil, putting paid all debts of honor, revenge -- those are natural reactions to me. Kicking ass first, taking names later. That's a way of life. The wrong way, but it appeals to men and women everywhere, because they all want to be God.
As to turning the other cheek, as with most of the parables of Jesus, He seems to me to be talking to us at a level much deeper than we seem to prefer. To me, He was talking about our reaction to injustice. Only God can (and will, eventually) forge good out of evil. Man cannot. He also told His disciples that they should render unto Caesar what was Caesar's, and He told them to obey man's law. As Christians, they should not hate, they should no longer "take revenge" on those who wrong them. They should, in fact, forgive them as they forgive themselves. I may do things and not like myself much for having done them, and I may have to suffer my penance(both spiritual and earthly) as a result. But I must forgive myself. Moreover, I must treat others in the same manner when they do the same. I do not have the option of hating them and still calling myself a Christian.
He never said that as members of a civil society with a constituted legal authority, that we, when authorized by that civil authority, should not lawfully punish those who've broken the law as long as we do so in accordance with the law. Forgiveness is our action with respect to the attitude we choose to have toward another. It doesn't necessarily restrain other appropriate actions we must take against a wrongdoer as human beings living in a civil society.
I've heard before the argument that forgiveness can come only with repentance. It makes logical sense if you equate forgiveness with restoring your relationship with the transgressor to the same place as it existed before he committed his wrongful acts. I don't. As a Christian, I don't find that qualifier to be persuasive, and, as a practical man who's spent his life as an advocate for sometimes less-than-sincere human beings, I realize that I have no way of judging whether a man's professed repentance is or is not sincere. I can't judge that, only God can. Therefore, I'm left with the task of doing the only thing that I can do with any certainty: forgiving the transgressor. I may also sue him in civil court, or turn him over to civil authorities for criminal punishment in accordance with man's laws, or cut off all contact with him for the good of my well-being and/or the well-being of others (my children, for instance). However, I can't hate him and I must forgive him.
Tough issues.
Tides by Sara Teasdale
Where the starlike sea gulls soar;
The sun was keen and the foam was blowing
High on the rocky shore.
But now in the dusk the tide is turning,
Lower the sea gulls soar,
And the waves that rose in resistless yearning
Are broken forevermore.
Stones taught me to fly
Love taught me to lie
Life taught me to die
So it's not hard to fall
When you float like a cannonball