C. S. Lewis is often the first Christian writer a modern reader picks up. But Lewis himself never wanted to be the last. Again and again he sent his readers back past himself to older books — the classics of the faith that had shaped him, many of them centuries old. If you have been helped by Lewis and want to know where to go next, the best answer is the answer he gave: read the books he read.

This guide introduces seven of them, every one of which is free to read in the Ochorus library. Lewis’s own books are still in copyright, so we describe his thought rather than quote it. But the writers below are long out of copyright, and they can speak for themselves.

Why read old books at all?

In 1944 Lewis wrote an introduction to a new English translation of Athanasius’ On the Incarnation, and in it he made a case that has become famous. Every age, he argued, has its own blind spots — assumptions so widely shared that nobody notices them. We cannot see our own; but we can see other people’s. Reading only new books is like listening to one side of a conversation that has been going on for two thousand years. The old books do not have our mistakes. They have different ones, and the contrast lets us see both. So he urged his readers to keep the old books in their diet as a matter of habit, letting the voices of earlier centuries regularly interrupt the chorus of their own.

Scripture had given the same counsel long before. “Stand ye in the ways, and see, and ask for the old paths, where is the good way, and walk therein, and ye shall find rest for your souls” (Jeremiah 6:16). “Remember the days of old, consider the years of many generations: ask thy father, and he will shew thee; thy elders, and they will tell thee” (Deuteronomy 32:7). The church is not a club founded last year. It is a family with a long memory, and we are “compassed about with so great a cloud of witnesses” (Hebrews 12:1). The old books are how those witnesses still speak.

1. George MacDonald — Unspoken Sermons

No writer mattered more to Lewis than George MacDonald, the Scottish preacher, novelist and poet who died in 1905. Lewis bought MacDonald’s fantasy Phantastes on a railway bookstall in 1916, as a teenage atheist, and found in it a quality of holiness he could not name; years later he called MacDonald his master, compiled an anthology of his writings, and made him the guide in The Great Divorce.

The best place to meet MacDonald the Christian teacher is Unspoken Sermons, three series of meditations on the words of Jesus and the Fatherhood of God. They are demanding, searching, and full of an almost overwhelming sense of God’s goodness. One opens:

The hardest, gladdest thing in the world is, to cry Father! from a full heart.

George MacDonald, “Abba, Father!”

That sermon takes its text from Paul: “For ye have not received the spirit of bondage again to fear; but ye have received the Spirit of adoption, whereby we cry, Abba, Father” (Romans 8:15). A word of caution is fair. MacDonald hoped that God’s love would at last redeem every soul, and he rejected the doctrine of the atonement as it was commonly preached in his day. Lewis loved him without following him on the first point, and evangelical readers will want to read him with discernment. But few writers make the love of God feel so near.

2. G. K. Chesterton — Orthodoxy and The Everlasting Man

When Lewis was still an unbeliever in his twenties, he read G. K. Chesterton’s The Everlasting Man, and for the first time saw the whole sweep of human history in a Christian light. It made sense, he found, in a way the alternatives did not, and he later gave it a large share of the credit for his return to faith. The book is a reply to the idea that humanity is merely a clever animal and that Christianity is just one more myth among many. Chesterton argues the opposite: that man is a strange and unique creature, and that the story of Christ stands alone.

Before it, Chesterton had written Orthodoxy (1908), the account of how he himself came to believe — not by escaping into faith, but by discovering that Christianity fitted the shape of the world better than any rival. It is witty, paradoxical and joyful, and near its close it says this:

Joy, which was the small publicity of the pagan, is the gigantic secret of the Christian.

G. K. Chesterton, Orthodoxy

Readers who love Lewis’s reasonableness will find its root here. Chesterton shows that the faith “once delivered unto the saints” (Jude 3) is not a cage for the mind but a home for it.

3. Athanasius — On the Incarnation

On the Incarnation was written in the fourth century by Athanasius of Alexandria, who spent his life defending the full divinity of Christ against those who would make Him less than God. It is short, clear and astonishingly fresh — a young man’s explanation of why the Word of God became flesh, and what His death and resurrection achieved. Ochorus carries Archibald Robertson’s public-domain translation; Lewis’s own introduction belongs to a later edition and is still in copyright. At the heart of the book is one of the most famous sentences in Christian theology:

For He was made man that we might be made God.

Athanasius, On the Incarnation

Athanasius means, as the whole book shows, not that we cease to be creatures, but that we are brought by grace to share in the life of God — as Peter puts it, to be “partakers of the divine nature” (2 Peter 1:4). Lewis believed that a reader who could manage a little hard thinking would find this ancient book more nourishing than many modern ones, and he was right.

4. Augustine — Confessions

Lewis wrote much about a longing that nothing in this world can satisfy, and about pride as the root of every other sin. On both themes he stands in the line of Augustine of Hippo, whose Confessions is the first great spiritual autobiography. It tells the story of a brilliant, restless young man who tried philosophy, ambition and pleasure, and found rest only in God. It begins with a prayer:

Thou madest us for Thyself, and our heart is restless, until it repose in Thee.

Augustine, Confessions

Lewis’s own conversion story, told in his autobiography, follows a strikingly similar path. Reading the two side by side is one of the best ways to see that Lewis was not inventing a new kind of Christianity, but walking an old road.

5. John Bunyan — The Pilgrim’s Progress

Lewis’s first Christian book, written soon after his conversion, was an allegory of his own spiritual journey, and he borrowed its shape openly from John Bunyan. The Pilgrim’s Progress follows Christian from the City of Destruction to the Celestial City, through the Slough of Despond, Vanity Fair and the Valley of the Shadow of Death. Its most beloved scene is the moment at the cross:

So I saw in my dream, that just as Christian came up with the cross, his burden loosed from off his shoulders, and fell from off his back, and began to tumble, and so continued to do till it came to the mouth of the sepulchre.

John Bunyan, The Pilgrim’s Progress

It is the gospel in a picture: “Come unto me, all ye that labour and are heavy laden, and I will give you rest” (Matthew 11:28). Late in life Lewis wrote an appreciative essay on Bunyan, praising the plain strength of his English. If you have children, the library also has editions of The Pilgrim’s Progress for children and for teens.

6. Thomas à Kempis — The Imitation of Christ

Among the old devotional books Lewis commended was The Imitation of Christ, attributed to Thomas à Kempis, a fifteenth-century monk. It is a book to read slowly, a few lines at a time — short chapters on humility, inward peace, the danger of curiosity, and the love of Jesus above all things. Few books have been read by so many Christians of so many traditions. One of its most beautiful passages takes up the words of Christ:

Follow Me. I am the Way, the Truth, and the Life. Without the Way, there is no going. Without the Truth, there is no knowing. Without the Life, there is no living.

Thomas à Kempis, The Imitation of Christ

Thomas is expounding John 14:6: “Jesus saith unto him, I am the way, the truth, and the life: no man cometh unto the Father, but by me.” Lewis’s chapters on pride and humility are the modern descendants of books like this.

7. William Law — A Serious Call to a Devout and Holy Life

Finally, William Law’s A Serious Call to a Devout and Holy Life (1728), a book Lewis read and admired. It is a bracing challenge to anyone content with a Sunday religion: Law insists that the whole of life — work, money, time, meals, conversation — is to be given to God. It was this book that awoke both John Wesley and Samuel Johnson to the seriousness of faith. Law defines his terms at the outset:

Devotion signifies a life given, or devoted, to God.

William Law, A Serious Call

It is Paul’s plea in eighteenth-century dress: “I beseech you therefore, brethren, by the mercies of God, that ye present your bodies a living sacrifice, holy, acceptable unto God, which is your reasonable service” (Romans 12:1).

How to begin

You do not have to read all seven at once. Here is one simple way in.

  • If you want to understand the faith: start with On the Incarnation, then Orthodoxy.
  • If you want a story: start with The Pilgrim’s Progress, then the Confessions.
  • If you want to pray and grow: read a chapter of The Imitation of Christ each morning, and one of the Unspoken Sermons each Sunday.
  • If you want to be challenged: read A Serious Call — slowly.

And whichever you choose, read it alongside Scripture, the oldest book of all, which these writers loved above everything they wrote. “Thy word is a lamp unto my feet, and a light unto my path” (Psalm 119:105). For an introduction to Lewis’s own teaching — summarised in our words, not his — see The Key Teachings of C. S. Lewis, and his life on his author page.