What 1950 book by C.S. Lewis collected his wartime BBC talks on Christianity?

Mere Christianity is the 1950 book that collected C.S. Lewis’s wartime BBC talks on Christianity.

The book developed from a series of radio broadcasts Lewis gave during the Second World War. The talks were first published in separate forms, including Broadcast Talks and Christian Behaviour, before being revised and brought together as Mere Christianity in 1950.

Lewis’s aim was to explain what he presented as common Christian beliefs shared across major traditions. The book discusses morality, human nature, belief, and Christian doctrine in accessible prose. It was not intended as a complete systematic theology or as a replacement for the distinct teachings of individual denominations.

The title is sometimes mistaken for a description of Lewis’s personal church affiliation. Lewis was an Anglican, and the book’s argument draws on broadly Christian ideas while deliberately emphasizing shared ground. Its broadcast origin also explains its conversational tone.