Americans are wealthier, smarter, and more beautiful than ever before, but we are also more depressed, anxious, and lonely. How can this be? The answer for many of us is perfectionism. Perfectionists pursue flawlessness and often reach great heights as a result, but we ultimately fall frustratingly short of our ideal. Christian perfectionists turn frustration into despair, because Christ commands us to "be ye therefore perfect, even as your father...