Which Christian allegorical book did C.S. Lewis publish in 1942?

C.S. Lewis published The Screwtape Letters in 1942. The book is a Christian apologetic work presented as a series of fictional letters from Screwtape, a senior demon, to his inexperienced nephew Wormwood.

Through the demons’ advice, Lewis explores temptation, pride, distraction, spiritual complacency, and the ways ordinary habits can shape moral life. The unusual perspective makes the book satirical: readers are expected to recognize the distortions in the demons’ reasoning.

The letters first appeared in the Anglican newspaper The Guardian before being collected as a book. Lewis’s wartime radio broadcasts and theological writing made him increasingly prominent in Britain during the same period.

The book is often confused with Mere Christianity, which developed from Lewis’s wartime broadcasts and was published in collected form later. The Screwtape Letters is the work with the demon-to-demon correspondence format.