What title is given to C.S. Lewis’s wartime radio talks about Christianity?

C.S. Lewis’s wartime radio talks about Christianity were collected under the title Mere Christianity.

The talks were broadcast by the BBC during the Second World War, beginning in 1941. Lewis aimed to explain shared Christian beliefs in clear language rather than defend one particular denomination. The broadcasts were later revised and published as books, eventually forming Mere Christianity.

The work is organized around themes including morality, Christian belief, and the development of Christian character. Its title refers to what Lewis called the common or central beliefs held across historic Christianity. The book became one of Lewis’s most influential works of apologetics and helped establish his reputation as a public Christian writer.