What was the title of the radio talks by C.S. Lewis later published as a book in 1952?

The radio talks by C.S. Lewis were later published as Mere Christianity in 1952. Lewis originally delivered the talks for the BBC during the Second World War, beginning in 1941.

The broadcasts addressed shared Christian beliefs rather than the distinctive doctrines of one denomination. Lewis organized the material around themes such as morality, human nature, Christian belief, and the meaning of conversion.

The book was assembled from several broadcast series. Earlier printed forms included The Case for Christianity, Christian Behaviour, and Beyond Personality, which were later brought together and revised into the familiar volume titled Mere Christianity.

A frequent confusion is that Mere Christianity was first written as a conventional book. Its origin was broadcast speech, so the prose retains a direct, conversational quality. The work became one of Lewis’s best-known examples of Christian apologetics and has remained widely read since its mid-century publication.