What medium first delivered the talks later collected as C.S. Lewis’s Mere Christianity?

Mere Christianity began as BBC radio broadcasts by C.S. Lewis during the Second World War.

Lewis delivered the talks between 1941 and 1944 for British radio audiences. Their purpose was to explain central Christian ideas in accessible language rather than to promote one particular denomination. The broadcasts made Lewis widely known beyond academic and literary circles.

The talks were later revised and gathered into books. The familiar title Mere Christianity was used for the collected volume published in 1952. Its sections discuss morality, Christian belief, and practical Christian conduct.

It is easy to confuse the broadcasts with university lectures because Lewis was an Oxford academic, but this series was created for radio listeners. The wartime setting also shaped its direct, conversational tone. The book remains one of Lewis’s most widely read works of Christian apologetics.