C.S. Lewis began the BBC radio broadcasts later collected as Mere Christianity in 1941.
The first series was broadcast during the Second World War, when Lewis spoke about basic Christian beliefs to a general audience. His talks were designed for listeners from different church backgrounds rather than for specialists in theology. Their direct, conversational style helped make him a widely recognized public Christian voice.
Further broadcast series followed in 1942 and 1944. The talks were revised and assembled in book form, with the title Mere Christianity. The book’s final structure includes “Right and Wrong as a Clue to the Meaning of the Universe,” “What Christians Believe,” and “Christian Behaviour.”
Mere Christianity is not a denominational manual and does not attempt to settle every disagreement between Christian traditions. Instead, Lewis presents what he calls the common or central beliefs shared by historic Christianity.