Which C.S. Lewis work presents Christianity through conversations based on wartime radio broadcasts?

Mere Christianity presents C.S. Lewis’s account of Christianity through material based on wartime radio broadcasts. The broadcasts were delivered by Lewis for the BBC during World War II and later revised into book form.

The first broadcast series, titled Broadcast Talks, began in 1941. Lewis followed it with Christian Behaviour in 1942 and Beyond Personality in 1944. These talks were eventually gathered and edited as Mere Christianity, published in book form in 1952.

The work is organized around basic Christian beliefs shared across major traditions. Lewis discusses morality, human nature, repentance, and the Christian understanding of God and Christ. He intended the book as a common introduction rather than a defense of one denomination.

A frequent mix-up is to identify Mere Christianity as a transcript of a single radio lecture. It is instead a revised compilation of several broadcast series. The title refers to the shared core of Christian belief, not to a separate church or denomination.