Which C.S. Lewis book records radio talks later published as Mere Christianity?

Broadcast Talks is the C.S. Lewis book that first collected radio talks later associated with Mere Christianity.

Lewis delivered the talks for the BBC during the Second World War. The first series was broadcast in 1941, followed by further series in 1942 and 1944. He aimed to explain shared Christian beliefs in accessible language to a broad British audience rather than present a specialized academic argument.

The first collection appeared in 1942 under the title Broadcast Talks. A second volume, Christian Behaviour, followed in 1943, and Beyond Personality appeared in 1944. These books were later revised and combined as Mere Christianity, a title that became much more familiar to modern readers.

Because Mere Christianity is now the best-known title, readers sometimes identify it as the original broadcast collection. Historically, however, Broadcast Talks names the first published volume. Lewis’s radio work helped establish him as a public religious writer and brought his arguments to listeners beyond universities and literary circles.