Which C.S. Lewis book presents his 1941–1944 BBC talks on Christianity?

Mere Christianity presents C.S. Lewis’s 1941–1944 BBC talks on Christianity.

The broadcasts began during the Second World War, when Lewis was invited to speak to a wide radio audience. He explained basic Christian ideas in accessible language rather than presenting a detailed defense of one denomination. The talks were later revised and published in book form.

The title refers to the shared core of belief found across major Christian traditions. The book is organized into sections commonly known as “Right and Wrong as a Clue to the Meaning of the Universe,” “What Christians Believe,” and “Christian Behaviour,” followed by a discussion of personality and the Trinity.

Mere Christianity is often confused with The Problem of Pain, another Lewis work of apologetics. The earlier book focuses especially on suffering and the problem of evil, while Mere Christianity grew directly from the wartime radio talks.