Which C.S. Lewis book collects radio talks first broadcast during World War II?

Mere Christianity collects C.S. Lewis’s radio talks first broadcast during World War II.

The talks were delivered for the BBC between 1941 and 1944, when Lewis addressed a broad British audience about shared Christian beliefs. They were later revised and published in book form, with the title Mere Christianity referring to the common core Lewis believed was held by major Christian traditions.

The book is arranged in four parts: “Right and Wrong as a Clue to the Meaning of the Universe,” “What Christians Believe,” “Christian Behaviour,” and “Beyond Personality.” Its conversational style helped make Lewis a major popular Christian apologist.

The work is not a transcript of one single broadcast series in its original form; it developed from several related broadcast sets and later revisions. The Problem of Pain is also apologetic, but it was published as a separate book in 1940.