A prophet is without honor not only in his own town but equally in his own time. Only in hindsight can we appreciate the accuracy of his prophecies.

This summer we celebrate the one-hundredth anniversary of the birth of C. S. Lewis, and in hindsight it becomes startlingly clear that this tweedy, pipe-smoking scholar was not only a clever author of children's tales and a keen apologist, but also a true prophet for our postmodern age. Lewis might seem an unlikely candidate for the role, not being a theologian but an English professor, and what's more, a convert late in life. What was it that made him such a keen observer of cultural and intellectual trends?

For me, the question has intense personal significance. Twenty-five years ago, my friend Tom Phillips read me "The Great Sin," a chapter in Lewis's Mere Christianity dealing with pride. The words pierced the heart of this White House hatchet man, and the book became instrumental in my conversion.

The ministry of Prison Fellowship is likewise indebted to Lewis. His essay "The Humanitarian Theory of Punishment" (1954) anticipated the failure of policies seeking to cure or deter crime. Such theories may appear humanitarian, Lewis argued, but they actually reduce the criminal to an object to be manipulated for social goals.

By contrast, a biblical understanding treats the individual as a moral agent, whose actions deserve either praise or blame. Punishment is not about pragmatic goals but about justice.

Lewis's Miracles (1947) was likewise prophetic, penned before most Christians were aware of the emerging philosophy of naturalism, the belief that there is a naturalistic explanation for everything in the universe. Lewis demonstrated that naturalism is self-destructing: If nature ...