In a recent sermon, my pastor told of a frantic phone call he received from his mother several years ago. "Peter, you must come home right away!" she said. His elderly father had been knocked out, badly cut, and relieved of thousands of dollars. He was lying in critical condition in a local hospital. Peter caught the next plane home and congratulated the men who did the deed.

"You see," he explained, "they were cardiac specialists. By operating so quickly after his heart attack, they saved my father's life."

Last summer I too had an encounter with masked men bearing scalpels. A surgeon operated on my foot, not my heart, and my life was never in danger. Yet the horizontal recovery time did give me a chance to reflect on pain that we choose voluntarily, sometimes for our own good and sometimes to our peril.

While rehabilitating, I often did exercises that hurt because I knew that working through the soreness would allow my foot to regain its usefulness. On the other hand, ...