There was a time when the field of medicine, psychiatry, or even psychology was uncomfortable with looking too closely at the issue of forgiveness. Forgiveness is often perceived as an issue of faith. But today, forgiveness has become a widely studied topic in the clinical field.
In the late 1990s, there were only 58 published clinical studies on forgiveness. Today there are now almost 1,500 clinical studies on it. It's a huge leap for the clinical role of forgiveness in psychotherapy. There is even a foundation called Campaign for Forgiveness Research.
In an article by NEWSWEEK, a statement was made similar to the truth the psalmist in Scriptures knew long ago: "Persistent unforgiveness is part of human nature, but it appears to work to the detriment not just of our spiritual well being but our physical health as well."
Science and medicine is now accepting that unforgiveness, resentment, anger, and guilt all have physiological/medical effects on the person. They can produce distress and illness; a state of "bones wasting away" (Psalm 32:3).
If you wish to be well, the Rx is to forgive. When you forgive someone else for something he or she did to you, you change your physiology and your psychology.