Who among us has never wondered if there might not really be a tempter sitting on our shoulders or dogging our steps? C.S.Lewis dispels all doubts. In The Screwtape Letters, one of his bestselling works, we are made privy to the instructional correspondece between a senior demon, Screwtape, and his wannabe diabolical nephew Wormwood. As mentor, Screwtape coaches Wormwood in the finer points, tempting his "patient" away from God. Each letter is a masterpiece of reverse theology, giving the reader a inside look at the thinking and means of temptation. Tempters, according to Lewis, have two motives: the first is fear of punishment, the second a hunger to consume or dominate other beings. On the other hand, the goal of the Creator is to woo us unto hiself or to transform us through his love from "tools into servants and servants into sons." It is the dichotomy between being consumed and subsumed completely into another"s identity or being liberated to be utterly ourselves that Lewis...