Which 1942 C.S. Lewis book retells Christian ideas through a senior demon’s letters?

The Screwtape Letters is C.S. Lewis’s 1942 book that presents Christian ideas through a senior demon’s letters.

The book consists of fictional letters from Screwtape, an experienced demon, to his inexperienced nephew Wormwood. Screwtape offers advice on tempting a human subject, allowing Lewis to examine pride, distraction, self-deception, prayer, and moral choice from an intentionally inverted viewpoint.

The work was first published in book form in 1942 after portions had appeared in the Anglican newspaper The Guardian. Its epistolary structure gives the book a distinctive voice, but its purpose is satirical and theological rather than a claim that demons literally wrote the text.

The title can be confused with Lewis’s other apologetic books, such as Mere Christianity and Miracles. Those works use direct argument, whereas The Screwtape Letters uses imaginative satire.