Dr. Richard Selzer is a surgeon and a favorite author of mine. He writes the most beautiful and compassionate descriptions of his patients and the human dramas they confront. In his book Letters to a Young Doctor, he said that most young people seem to be protected for a time by an imaginary membrane that shields them from horror. They walk in it every day but are hardly aware of its presence. As the immune system protects the human body from the unseen threat of harmful bacteria, so this mythical membrane guards them from life-threatening situations. Not every young person has this protection, of course, because children do die of cancer, congenital heart problems, and other disorders. But most of them are shielded—and don’t realize it. Then, as years roll by, one day it happens. Without warning, the membrane tears, and horror seeps into a person’s life or into the life of a loved one. It is at this moment that an unexpected theological crisis presents itself.