Forgiveness is typically defined as the process of concluding resentment, indignation or anger as a result of a perceived offense, difference or mistake, and ceasing to demand punishment or restitution. The Oxford English Dictionary defines forgiveness as 'to grant free pardon and to give up all claim on account of an offence or debt'. The concept and benefits of forgiveness have been explored in religious thought, the social sciences and medicine.
Forgiveness may be considered simply in terms of the person who forgives including forgiving themselves, in terms of the person forgiven and/or in terms of the relationship between the forgiver and the person forgiven. In some contexts, forgiveness may be granted without any expectation of restorative justice, and without any response on the part of the offender (for example, one may forgive a person who is incommunicado or dead). In practical terms, it may be necessary for the offender to offer some form of acknowledgment, apology, and/or restitution, or even just ask for forgiveness, in order for the wronged person to believe himself able to forgive.
Most world religions include teachings on the nature of forgiveness, and many of these teachings provide an underlying basis for many varying modern day traditions and practices of forgiveness. Some religious doctrines or philosophies place greater emphasis on the need for humans to find some sort of divine forgiveness for their own shortcomings, others place greater emphasis on the need for humans to practice forgiveness of one another, yet others make little or no distinction between human and/or divine forgiveness.
Prior to the 1980s, forgiveness was a practice primarily left to matters of faith. Although there is presently no consensus psychological definition of forgiveness in the research literature, agreement has emerged that forgiveness is a process and a number of models describing the process of forgiveness have been published, including one from a radical behavioral perspective .
Dr. Robert Enright from the University of Wisconsin-Madison founded the International Forgiveness Institute and is considered the initiator of forgiveness studies. He developed a 20-Step Process Model of Forgiveness. Recent work has focused on what kind of person is more likely to be forgiving. A longitudinal study showed that people who were generally more neurotic, angry and hostile in life were less likely to forgive another person even after a long time had passed. Specifically, these people were more likely to still avoid their transgressor and want to enact revenge upon them four and a half years after the transgression. Studies show that people who forgive are happier and healthier than those who hold resentments. The first study to look at how forgiveness improves physical health discovered that when people think about forgiving an offender it leads to improved functioning in their cardiovascular and nervous systems.  Another study at the University of Wisconsin found the more forgiving people were, the less they suffered from a wide range of illnesses. The less forgiving people reported a greater number of health problems. 
The research of Dr. Fred Luskin of Stanford University shows that forgiveness can be learned. In three separate studies, including one with Catholics and Protestants from Northern Ireland whose family members were murdered in the political violence, he found that people who are taught how to forgive become less angry, feel less hurt, are more optimistic, become more forgiving in a variety of situations, and become more compassionate and self-confident. His studies show a reduction in experience of stress, physical manifestations of stress, and an increase in vitality. One study has shown that the positive benefit of forgiveness is similar whether it was based upon religious or secular counseling as opposed to a control group that received no forgiveness counseling.
The child, being immature and lacking in the fuller understanding of the depth of the child-father relationship, must frequently feel a sense of guilty separation from a father's full approval, but the true father is never conscious of any such separation. Sin is an experience of creature consciousness; it is not a part of God's consciousness.
"Your inability or unwillingness to forgive your fellows is the measure of your immaturity, your failure to attain adult sympathy, understanding, and love. You hold grudges and nurse vengefulness in direct proportion to your ignorance of the inner nature and true longings of your children and your fellow beings. Love is the outworking of the divine and inner urge of life. It is founded on understanding, nurtured by unselfish service, and perfected in wisdom."
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- Maltby, J., Wood, A. M., Day, L., Kon, T. W. H., Colley, A., and Linley, P. A. (2008). Personality predictors of levels of forgiveness two and a half years after the transgression. Journal of Research in Personality, 42, 1088-1094.
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