The exhortation to love one's enemies stands out as one of the most challenging of all of Christ's teachings, as the contents and obligations of such love are elusive, and their practical fulfillment is inescapably arduous. Between oneself and one's enemy stand an array of injustices and injuries that arouse layered emotional reactions, which often persist over extended periods of time. To love one's enemy is thus to rise above hurt, anger, resentment, and even hatred, and to offer instead the gift of mercy—to forgive.

In Pardon and Peace, Fr. John B. Burns provides a rich, interdisciplinary study of healing through interpersonal forgiveness, combining the findings of modern clinical psychology and the insights of St. Thomas Aquinas's theological anthropology. Utilizing the field-leading work of psychologist Robert Enright, Burns first outlines the tremendous progress made within the field of psychology in understanding interpersonal forgiveness as a process that moves in stages and inherently involves a range of emotions. He then incorporates the philosophical and theological gains of Aquinas, uniting and extending their shared lines of inquiry in order to develop a theological account of interpersonal forgiveness and to examine the place of forgiveness within a theology of healing. As Burns shows, the mutual fruitfulness of dialogue between psychology and theology furnishes new conclusions for both fields, holding promise not only for a better understanding of interpersonal forgiveness but also for its practical and pastoral applications.