Which 1933 book by C.S. Lewis was his first published work after becoming a Christian?

The Pilgrim’s Regress was C.S. Lewis’s first published work after becoming a Christian.

Published in 1933, The Pilgrim’s Regress is an allegorical novel subtitled An Allegorical Apology for Christianity, Reason and Romanticism. Lewis wrote it after his conversion and used a journey through a symbolic landscape to explore belief, reason, desire, and competing philosophies.

The title deliberately recalls John Bunyan’s seventeenth-century classic The Pilgrim’s Progress, but Lewis’s book is not a retelling. It reflects the intellectual and spiritual debates that shaped his own return to Christianity, including his changing views about reason and imagination.

Later apologetic works such as The Problem of Pain and Mere Christianity made Lewis more widely known. The Pilgrim’s Regress is earlier and more overtly literary, which can make it less familiar to general readers.