In the series, we’re excerpting summaries Ken Boa has produced over the years on classic works of literature. See the first post for a list of 16 classics every Christian should know.
The material contained in C. S. Lewis’s Mere Christianity was originally a series of radio messages aired by the British Broadcasting Corporation (BBC) during World War II.His first broadcasts, which aired in 1942–43, included The Case for Christianity and Christian Behavior. Beyond Personality was heard in 1944. These three works were combined later into the book Mere Christianity.
By the term “mere Christianity” Lewis was referring to the essence of Christianity rather than to its denominational manifestations … the beliefs that Christians share in common.
By the term “mere Christianity” Lewis was referring to the essence of Christianity rather than to its denominational manifestations. The term implies that there are particular biblical doctrines that distinguish Christianity. Lewis deals with basic, creedal orthodoxy—those essential elements revealed in Scripture and condensed in the great affirmations of the Apostles’ Creed and the Nicene Creed. Lewis seeks to delineate the beliefs that Christians share in common—the essentials of the faith. His Mere Christianity reflects the spirit of the famous statement: “In the essentials, unity; in the nonessentials, diversity; and in all things, charity.”1
The Hallway of Doors
Lewis introduces his work with an image of a hallway containing numerous doors leading into various rooms. He explains, “If I can bring anyone into that hall, I shall have done what I attempted. But it is in the rooms, not in the hall, that there are fires and chairs and meals. The hall is a place to wait in, a place from which to try the various doors, not a place to live in.” In other words, he argues that all believers in Christ can share the hall, but eventually each must discern which community’s door he or she will enter.
Lewis understood the biblical emphasis on unity within the true church, for he warns, “When you have reached your own room, be kind to those who have chosen different doors and to those who are still in the hall. If they are wrong, they need your prayers all the more; and if they are your enemies, then you are under orders to pray for them. That is one of the rules common to the whole house.”2 This admonition is in keeping with Paul’s in Romans 15:5–6:
Now may the God who gives perseverance and encouragement grant you to be of the same mind with one another according to Christ Jesus, so that with one accord you may with one voice glorify the God and Father of our Lord Jesus Christ.
The thesis of the first part (“book”) of Mere Christianity is that human awareness of goodness, justice, and fairness, as well as our own failings in those areas, provides the evidence that a personal and good God exists. Here is the heart of Lewis’s argument:
Christianity simply does not make sense until you have faced the sort of facts I have been describing. … It is after you have realized that there is a real Moral Law, and a Power behind the law, and that you have broken that law and put yourself wrong with that Power—it is after all this, and not a moment sooner, that Christianity begins to talk. When you know you are sick, you will listen to the doctor. When you have realized that our position is nearly desperate you will begin to understand what the Christians are talking about. They offer an explanation of how we got into our present state of both hating goodness and loving it. … They tell you how the demands of this law, which you and I cannot meet, have been met on our behalf, how God Himself becomes a man to save man from the disapproval of God.
When you know you are sick, you will listen to the doctor. —C.S. Lewis
The Case for Christianity
Book 2 of Mere Christianity focuses on what Christians believe. Lewis begins with a presentation of the rival concepts regarding God, and he observes that a majority of people “believe in some kind of God or gods.” However, people disagree on the sort of God they believe in. Pantheists, for example, would say that God is everything and that the whole world is a self-expression of his nature. For them, good and evil are only illusions caused by our relative perspective, and ultimately all things that exist constitute one unity.
Lewis asserts that if you do not take the distinction between good and bad very seriously, then it is easy to say that anything you find in this world is a part of God. But, of course, if you think some things are really bad, and God is really good, then you cannot talk that way. You must believe that God is separate from the world and that some of the things we see in it are contrary to his will.
Our Idea of Justice
The distinction between good and evil brings up another issue—the idea of justice. Lewis reveals his own struggle with the problem of evil before coming to faith in Christ and points to his awareness of justice and injustice as indicative of God’s existence (and not only that, but of a personal, good, and righteous God):
My argument against God was that the universe seemed so cruel and unjust. But how had I got this idea of just and unjust? A man does not call a line crooked unless he has some idea of a straight line. What was I comparing this universe with when I called it unjust?
A man does not call a line crooked unless he has some idea of a straight line. —C.S. Lewis
Atheism turns out to be too simple. If the whole universe has no meaning, we should never have found out that it has no meaning ; just as, if there were no light in the universe and therefore no creatures with eyes, we should never know it was dark. Dark would be a word without meaning.
The Existence of Evil
Next, Lewis discusses the distinctly Christian concept of evil as being a distortion of the good. The fact that this distortion occurred relates to human free will. Free will, in turn, gives rise to our dignity and capacity for true relationship with God. (It wouldn’t be much of a relationship if God had just programmed us as machines that chant, “I love you.”)
The Authenticity of Jesus
Next, Lewis discusses the authenticity of Jesus Christ. Perhaps the best known-paragraph in Mere Christianity deals with what Lewis termed the “trilemma”:
I’m trying here to prevent anyone saying the really foolish thing that people often say about Him: “I am ready to accept Jesus as a great moral teacher, but I don’t accept His claim to be God.” This is the one thing we must not say. A man who was merely a man and said the sort of things that Jesus said would not be a great moral teacher. He would either be a lunatic—on a level with the man who says he is a poached egg—or else he would be the Devil of Hell. You must make your choice. Either this man was, and is, the Son of God: or else a madman or something worse. You can shut Him up for a fool, you can spit at Him and kill Him as a demon; or you can fall at His feet and call Him Lord and God. But let us not come with any patronizing nonsense about His being a great human teacher. He has not left that open to us. He did not intend to.
You must make your choice. Either this man was, and is, the Son of God: or else a madman or something worse.
Lewis goes on to discuss the issue of repentance. He writes, “Fallen man is not simply an imperfect creature who needs improvement; he is a rebel who must lay down his arms …” Lewis makes the case for why Jesus had to come and how only the suffering and death of the “perfect penitent” could save us from our predicament.
Infused with His Life
Lewis concludes this section on a practical note, explaining that all people are moving toward either glorification or damnation, toward fellowship with God or eternal divorce and separation. For those drawing closer to Him, He has promised to infuse His life into us: “In Christ a new kind of man appeared … [The] Christian thinks any good he does comes from the Christ-life inside him.” This discussion transitions readers to the next section, on Christian morality/behavior.
In book 3 of Mere Christianity, Lewis employs the analogy of a ship to explain morality as consisting of three categories:
- Personal ethics/morality: How can one keep the ship from sinking while at sea?
- Social ethics/morality: How can one keep from colliding with other ships while at sea?
- Foundational ethics/morality (also known as teleology–relating to moral purpose): Why is the ship at sea in the first place?
All three dimensions of morality, Lewis contends, connect into a cohesive whole. If we truncate the process and focus only on social morality (as some are apt to do), we have no access to the source of power (God) to attain the virtuous life Lewis is about to talk about. In other words, morality can be captured with three questions:
- Am I in harmony with God?
- Am I in harmony with myself?
- Am I in harmony with others?
An affirmative to the first question (relating to foundational ethics) enables the other two, and without harmony with God, the other two (personal and social morality) become impossible.
4 Cardinal Virtues
In the area of personal ethics (harmony with ourselves), Lewis discusses four cardinal virtues: prudence, temperance, justice, and fortitude. These were given by God to promote our well-being, not to become legalistic ends in themselves.3 Here are Lewis’s definitions of each, briefly:
- Prudence = “practical common sense”
- Temperance = “going the right length and no further” in all pleasures (not only in drink)
- Justice = fairness, honesty, truthfulness, and promise keeping (based on God’s own standard)
- Fortitude = two types of courage, “the kind that faces danger as well as the kind that ‘sticks it’ under pain”
3 Theological Virtues
Lewis also defines and discusses three theological virtues—charity (love), hope, and faith.
- Love: Love or charity is not an emotional feeling but a choice of the will, and Lewis memorably advises readers, “Do not waste time bothering whether you ‘love’ your neighbor; act as if you did. As soon as we do this we find one of the great secrets. When you are behaving as if you loved someone, you will presently come to love him.”
- Hope: Not merely wishful thinking, but a concrete certainty; rational and based on the historic events of Christ’s life, death, and resurrection; often experienced as a profound longing that is never fully satisfied in this world.
- Faith: “The art of holding on to things your reason has once accepted, in spite of your changing moods,” faith was not separate or distinct from reason in Lewis’s mind.
All three of these virtues, Lewis insists, come only from God; we cannot produce them on our own.
Do not waste time bothering whether you “love” your neighbor; act as if you did. … When you are behaving as if you loved someone, you will presently come to love him. —C.S. Lewis
The last “book” of Mere Christianity contains many gems from Lewis as he addresses topics ranging from time to the Trinity to the question of whether Christianity is hard or easy. Lewis emphasizes that Christians are people who are not being merely improved but transformed. This requires a submission and death to self that we may at first fear, but in the end, it’s the best thing for us—better than we could imagine for ourselves.
“The more we get what we now call ‘ourselves’ out of the way and let Him take us over, the more truly ourselves we become,” Lewis says. “It is no good trying to ‘be myself’ without Him. The more I resist Him and try to live on my own, the more I become dominated by my own heredity and upbringing and surroundings and natural desires.”
In other words, as we become more like Christ, we become more uniquely the persons we were meant to be. When we give up ourselves, we will find our real selves.
We should keep back nothing, Lewis argues. After all, nothing that we have not already given away will really be ours. In this process, God is not asking us to forego our passions, but to passionately love Him and know true passion and purpose in all of life.
The more we get what we now call “ourselves” out of the way and let Him take us over, the more truly ourselves we become.
- Sometimes falsely attributed to St. Augustine, the origin of this quote is Rupertus Meldenius (German Lutheran theologian), ca. 1627.
- As in the original printings of these summaries, we have dispensed with page numbers to make for a more pleasant read. Also, British English spellings have been changed to American English.
- In his section on the cardinal virtues, Lewis explains how the Christian’s character is forged by his or her choosing to live out these central virtues. I have noticed that our culture has shifted in dialogue from virtues to values. This change is a significant one. Virtues are embedded in a system of absolutes, while values are relative, contextualized, and no longer connected to an absolute structure.