C. S. Lewis (1898-1963) was a prolific author and a professor of literature at both Oxford and Cambridge Universities in the mid-20th century. Lewis is known today mostly for his books, which include both fiction (such as The Chronicles of Narnia, The Screwtape Letters, and the Space Trilogy) and nonfiction, especially works of Christian theology and apologetics. Miracles falls in the latter category, alongside other famous Lewis works like Mere Christianity and The Problem of Pain.

Lewis was born into a nominally Christian household in Belfast, Northern Ireland just before the turn of the 20th century, and was baptized into the Anglican Church of Ireland. As a teenager, however, he embraced skepticism and began considering himself an atheist. His early life revolved around reading and education, eventually leading him to enroll at University College in Oxford. His studies were interrupted by the First World War, in which Lewis served on the front lines, suffered injury, and lost his friend and roommate to a battlefield death. Back home in England, Lewis continued his studies and eventually became a tutor at Magdalen College, Oxford, where he would spend the majority of his academic career.