Which C.S. Lewis book collects four wartime radio talks about Christian belief?

Mere Christianity collects C.S. Lewis’s wartime radio talks about Christian belief.

The talks were broadcast by the BBC during the Second World War, beginning in 1941. Lewis spoke to a general audience rather than a specialist theological group, explaining shared Christian ideas in direct, conversational language. He later revised and combined the broadcasts into the book Mere Christianity.

The work is organized into four parts: “Right and Wrong as a Clue to the Meaning of the Universe,” “What Christians Believe,” “Christian Behaviour,” and “Beyond Personality.” Lewis argues from morality toward belief and then discusses central Christian doctrines and ethical questions.

The title does not mean a separate denomination. “Mere Christianity” refers to the common core of belief shared across historic Christian traditions. Readers sometimes confuse the book with The Problem of Pain, another Lewis work about Christianity, but that book addresses suffering rather than collecting the BBC broadcasts.