C.S. Lewis’s Mere Christianity was first published as a complete volume in 1952. The book developed from talks Lewis gave for BBC radio during the Second World War, when he presented basic Christian ideas to a broad British audience.
The original broadcasts were delivered in several series between 1941 and 1944. Lewis later revised and combined the material into three sections: “Right and Wrong as a Clue to the Meaning of the Universe,” “What Christians Believe,” and “Christian Behaviour.”
The title refers to the shared core of Christian belief rather than to one denomination. Because the radio talks came first, 1941 is often associated with the work’s origin, but 1952 is the publication year for the unified book. Mere Christianity became one of Lewis’s most influential works of Christian apologetics.