On one occasion he spoke at the Norfolk Aerodrome, northeast of Oxford. His audience consisted of members of the bomber squadrons which took off nightly to pound German fortifications on the continent. That Sunday night Lewis used as his sermon text Jesus' words from Matthew 16:24, "If any man come after me, let him deny himself, and take up his cross, and follow me." This was a hard text for men who were facing death, and Lewis knew it. In the sermon, he told the men what Jesus had undergone on their behalf -- "misunderstanding and loneliness and finally betrayal and death." He dramatically evoked the scene in the judgment hall, where the soldiers and Herod mocked and ridiculed Jesus. And then he recalled with vivid force the obscenity of the crucifixion scene.

He encouraged the soldiers to think about what they could do for Jesus; whatever it would be, it would have to be costly. Lewis very emotionally told the men the costs he had to pay to become a Christian. Oxford had tolerated his intellectual interest in Christianity, but once he became a practicing Christian he lost friends and was in many ways ostracized.

At the end of the sermon, Lewis returned to "the indignities and calamities Christ had endured" and how the soldiers (at Golgotha) had shouted "hypocrite!" "Serves him right!" "That's what he deserved!" "Dirty traitor!" As he spoke these words, Lewis vigorously gestured and raised and lowered his voice, giving full weight to the horrors and realities of the biblical story.

Stuart Babbage has commented that it is not surprising that Lewis "communicated," for this sermon (like many others) was powerful preaching, "born of intense and passionately felt emotion." When Lewis preached in wartime to soldiers, he was eager, passionate, and always demanded a verdict, a decision. He left it to God as to just what those decisions were.

Lewis' sermons in university churches were different, at least in style, but his passion and care were always evident. They were not "popular" preaching, but were rather more intellectual in form and theological in content. The only volume currently in print that contains his Oxford (three) and Cambridge (one) sermons is The Weight of Glory (Macmillan, revised and expanded 1980). It was first published in England (1949) as Transposition and Other Addresses. The sermons in this book are "Learning in War-Time" (1939), "The Weight of Glory" (1941), "Transposition" (1944) and "A Slip of the Tongue" (1956).

Three of Lewis' sermons were preached to churches in London and Northampton and published in Undeceptions (1971), later God in the Dock (1971). "Miracles" was delivered at St. Jude on the Hill Church, London, on November 26, 1942. "Miserable Offenders" was preached at St. Matthew's Church, Northampton, on April 7, 1945. "The Grand Miracle" was preached at St. Jude's Church, London, on November 26, 1942. "Miracles" is the most famous of these sermons, and from it Lewis developed several of the ideas contained in his later book Miracles (1947).