C.S. Lewis concludes his 1961 preface by describing how he developed these profound themes of sin and temptation in the Screwtape Letters:
Some have paid me an undeserved compliment by supposing that my Letters were the ripe fruit of many years’ study in moral and ascetic theology. They forgot that there is an equally reliable, though less credible, way of learning how temptation works. “My heart”–I need no other’s–“showeth me the wickedness of the ungodly.”
