C.S. Lewis first delivered the talks later adapted as Mere Christianity on BBC radio.
The talks were broadcast during the Second World War, beginning in 1941. Lewis spoke directly to a general audience rather than presenting a technical theological lecture. His clear, conversational style helped make Christian apologetics accessible to listeners across Britain during a period of national crisis.
The broadcasts were revised and published in book form in stages. The resulting work, Mere Christianity, appeared as a single volume in 1952. It presents what Lewis called the common or “mere” elements shared by the major Christian traditions, rather than arguing for one denomination.
The book is sometimes described as a transcript of the broadcasts, but Lewis edited and reshaped the material for print. It is also distinct from The Problem of Pain, his 1940 book about suffering and belief.