Harry Lee Poe, a professor of faith and culture at Union University in Jackson, Tenn., pores over the first 20 years of C. S. Lewis’s life in Becoming C. S. Lewis: A Biography of Young Jack Lewis (1898-1918), the first of a three-volume biography of Lewis by Poe.

This conversation has been edited for length and clarity.

Why did you decide to look so closely at these first 20 years of Lewis’s life?

Virtually all of Lewis’s biographers have puzzled over why he devoted most of his spiritual biography, Surprised by Joy, to his first 20 years. As I first began to read the letters of young Jack Lewis from the time when he first went away to school, I realized why Lewis thought his childhood and youth were so important in his conversion. During this period, he developed all of his major tastes about what he enjoyed in life and what he hated. Many of the ideas that he would pursue in both his scholarly work and his popular writings have their genesis in his teenage years. Whether books like The Allegory of Love and A Preface to Paradise Lost, or The Chronicles of Narnia and Mere Christianity, many of the ideas found in these books were topics of Lewis’s interest in letters to [lifelong friend] Arthur Greeves when he was 16 and 17.

What was the most surprising thing you learned while writing this book?

The two most surprising things I learned about C. S. Lewis while writing Becoming C. S. Lewis were the way his pleasure reading as a teenager provided him with a career and created a path along which his later conversion travelled. As far as his career was concerned, young Jack Lewis decided as a teenager that he would become a philosopher. There were no classical/philosophical positions open when he graduated from Oxford [so] he remained another year to do a second degree in English literature, which led to his teaching post at Oxford and later Cambridge. How could anyone do a college degree in only one year even if that person is extraordinarily intelligent? The answer is that Lewis had already done most of the reading for an Oxford degree in English literature in his pleasure reading.

As far as his conversion is concerned, the literature he read for pleasure touched him at a deeper level. The stories involved such values as beauty, love, fairness, honesty, courage, and nobility of spirit, which Lewis could not allow existed because he had become an atheist who believed that only the material universe existed. Yet, he had experienced these things. How could values exist if they are not material?

Why should fans of The Lion, the Witch and the Wardrobe as well as fans of Lewis's spiritual writings read this biography?

Great writers do not write about themselves, but they do write about what they know. The world in which Jack Lewis lived as a boy in Ulster and as a teenager with his tutor in Great Bookham, Surrey, forms the landscape of Narnia. In Becoming C. S. Lewis, readers will find the stuff out of which C. S. Lewis would later craft many of his most important works through the power of imagination interacting with experience.

Can you give a preview of the next two books in your biography series on Lewis?

The second volume will be The Making of C. S. Lewis: From Atheist to Apologist, 1919-1945. It deals with the complicated relationship between Lewis and Mrs. Moore, the mother of his friend with whom he kept house until her death in 1951, and how his conversion occurred in the context of their unusual household.

The final volume, The Completion of C. S. Lewis: From Bachelor to Widower, 1945-1963, will explore how Lewis left aside the rationalistic apologetics he had agreed to write at the request of others during World War II in order to return to the kind of apologetics he most wanted to write – stories. Soon after the first Narnia story was published, Mrs. Moore died. During the same general period, an American writer and former communist named Joy Davidman Gresham arrived in England with the purpose of meeting Lewis. In due course Jack and Joy married, had an extravagantly happy marriage, and then she soon died. At the end of World War II, an American correspondent had urged Lewis to write a book on prayer, to which he had responded that he thought it would be incredibly cheek of him. He did not know about prayer then. After the death of Joy, he did.