Book excerpt: Obsessive-compulsive disorder (OCD) is a relentless condition, the primary symptom being the occurrence of terrifying ideas, images, and urges that jump into a person's mind and return again and again, despite the individual's attempt to remove them. Christians who suffer from OCD may grapple with additional guilt, as the undesired thoughts are frequently of a spiritual nature. Yet people may be surprised to learn that some of the greatest leaders in Christian history also struggled with this malady. What did they experience? How did they cope? Were they able to overcome these tormenting, often violent, obsessions? Where did God fit into the picture? Ian Osborn shares the personal accounts of Martin Luther, John Bunyan, and Saint Thérèse of Lisieux, as well as his own story, in exploring how faith and science work together to address this complex issue.