Which C.S. Lewis work was adapted from his 1941–1944 radio broadcasts?

Mere Christianity was adapted from C.S. Lewis’s 1941–1944 radio broadcasts.

During the Second World War, Lewis delivered a series of talks for BBC radio. The broadcasts addressed basic Christian beliefs in accessible language for a broad audience. Their wartime setting helped make Lewis a familiar public voice, even though he was primarily an academic and writer.

The talks were later revised and assembled into books. The main sections became Broadcast Talks, Christian Behaviour, and Beyond Personality. These were collected in one volume as Mere Christianity, first published in 1952.

The title refers to the shared core of Christian belief rather than to one denomination. Lewis did not intend the work to replace church teaching or settle every theological dispute. Its purpose was to explain central ideas such as morality, forgiveness, faith, and Christian character in language ordinary listeners could understand.