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It’s been a long time since I first encountered this book, and I do believe my opinion of it has shifted after this later reading. Lewis is a winsome writer and wordsmith, and is easy to read and enjoy. However, I think in terms of introductory and/or apologetic treatments of the Christian faith, there are many better places to go these days. Clear strengths would be his ability to leverage analogies to explain a concept without relying on jargon or difficult definitions, as well as his treatment of ethical/moral issues. Clear weaknesses, in my opinion, would be his treatment of the atonement and much of the other theological work, which at times felt quite muddled, as well as a lack of engagement with the Bible.

However, faults aside, the enduring legacy of evangelicals recommending Mere Christianity is a testimony to the impact this book has had on countless lives. The Lord often seems to prefer to work and convey his true through weak and leak vessels.

Book I


In the preface, Lewis begins with what amounts to a defense of his non-sectarian approach in the book and why he left out discussion of certain doctrinal & ethical topics. On the whole, I think his approach is legitimate and it makes sense when discussion is focused on a non-christian to stat away from intramural disputes.

While Lewis explicitly discounts the idea, there is the danger of someone deciding to camp out in “Mere Christianity” and never going so far as to join a leaving, breathing, historical communion, from which the concept itself is derived.

I love his discussion of our tendency to ruin words by using them in a way that moves them from an objective reality to a subjective evaluation, leaving the language void of a word for what was formerly described.

Ever since I became a Christian I have thought that the best, perhaps the only, service I could do for my unbelieving neighbours was to explain and defend the belief that has been common to nearly all Christians at all times.

Chapter 1 - The Law of Nature

Everyone has a standard of behavior that they think is “right.” Even though there may be some differences across civilizations, there are remarkable commonalities as well. There is, it seems, a Law of Human Nature, to which we all feel more or less accountable. Elsewhere, Lewis refers to this as the Tao. What else is common is that we all fail to live up to our own standard consistently. With that - a conscience that testifies against our own actions - we have the start of an understanding of sin and fallen human nature. It’s possible that Romans 2:14-15 refers to this same phenomenon (although this is debated).

There is something above and beyond the ordinary facts of men’s behaviour, and yet quite definitely real — a real law, which none of us made, but which we find pressing on us.

Chapter 2 - Answering Objections

Here Lewis deals with the object that what he calls the Moral Law is just herd instinct, naturally conditioned impulses. However, this doesn’t account for the sense of “ought,” especially when faced with two competing impulses. Likewise, the fact that we render judgment on some culture’s morals as good or bad indicates that we perceive a standard by which to evaluate them. While certainly, human sin has corrupted and distorted this innate moral sense, by God’s common grace it is still preserved as an echo through human generations.

“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.

Chapter 3 - The Reality of the Law

There is a fundamental difference between what we call the “Laws of Nature,” which is a term to describe things that are, as they always are. Gravity always behaves a specific way, etc. To say something is not as it ought to be in nature is to render a judgment on its fitness for my purpose, but there is no “ought” that is missing. The Laws of Nature are really just the steady consistency of the sovereignty of God. On the other hand, when speaking of morality or the Laws of human nature, it’s clear that there is a distinction between “is” and “ought” and this means there is a law over us that is not simply a reflection of us.

But the most remarkable thing is that we all really agree about it.

Chapter 4 - What Lies Behind the Law

The question science can’t answer: Why is there anything rather than nothing? Does it have any meaning? Science works by observation and experimentation and is therefore unable to speak to what is behind the observations. However, the options are: materialist (chance, no explanation) and religious (a mind). The law of human nature we see in ourselves points to mind. There must be a mind behind the law of ought, and it is reasonable to say so.

A man does not call a line crooked unless he has some idea of a straight line.

Chapter 5 - We have cause to be uneasy

A few conclusions up to this point: 1) We should dismiss the idea of progress as indicating that if we have left behind God and religion we should never go back. If you’ve made a wrong turn somewhere, the only right move is to go back. 2) If the moral law indicates a mind behind reality, it also indicates that this mind is Good. And far from being a comfort, which it may be in its own right, it should in fact make us very uneasy, considering how we stray from the “ought” within us. 3) Bringing in Christianity is not a trick, but a helpful way of making sense of the reality discussed so far. Without that foundation set, that of there being a dilemma of moral lawgiver and broken laws, Christianity may not make a whole lot of sense.

If there is a controlling power outside the universe, it could not show itself to us as one of the facts inside the universe—no more than the architect of a house could actually be a wall or staircase or fireplace in that house.

Book II

Chapter 1 - The Rival Conceptions of God

Lewis breaks down the basic ideas about God thus:
God vs. No-God
Then among believers in God:
Good God vs God Beyond Good/Evil
Separate God vs Pantheists
If everything is God, then you can’t really distinguish between good and evil, since we clearly see evil and injustice.

So the question is, if God is good, why is there bad? Here Lewis first removes the escape hatch of just denying God’s existence at all. By that route, you have to presuppose a standard of Justice by which to judge the world unjust, but this standard would need to be above the world and thus invalidate the atheistic conception of reality.

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.

Chapter 2 - The Invasion

There are no simple answers, because reality is not simple, or obvious, but it is actually quite odd. This oddness is a characteristic of Christianity as well.

Given the universe we observe, there are really two live options: Christianity and Dualism. However, Dualism doesn’t hold up since to even speak of opposing sides of Good & Evil requires us to have a standard of judging good and evil, otherwise the difference between two sides is merge our preference.

So, rather than dualism, we have Good, and the evil existing as a rebellion against the good. Christianity is the story of a world in rebellion, and the church is effectively a saboteur in enemy-occupied territory.

Christianity agrees with Dualism that this universe is at war, but it does not think this is a war between independent powers: it thinks it is a civil war, a rebellion, and that we are living in a part of the universe occupied by the rebel.

Chapter 3 - The Shocking Alternative

So we have Satan as the power over the world, but only by God’s permission. Is Satan’s rebellion part of God’s will or against it? Yes. Lewis argues that God chooses to allow sin for the greater good of having creatures that exercise free will. He even gives the awkward phrase that God “deemed it worth the risk” to have free will. Certainly, it can be said that the creatures were free to choose sin or righteousness, so in that sense the free will argument stands. But does it go far enough? Did God “take a risk,” as Lewis puts it, or is the ultimate truth deeper than that? Presumably, God created knowing, not only that his creatures could fall, but indeed that they would fall. Reformed theologians would stress that God’s ultimate design was the manifestation of the rich glory of his nature in all its faces, which includes judgment and mercy.

The remainder of the chapter expounds God’s witness to the truth in conscience, in legend (what Lewis calls “good dreams”), and finally in Jesus, who claimed to be the divine Son of God. Here we find the famous Lord, Liar, Lunatic argument.

Free will, though it makes evil possible, is also the only thing that makes possible any love or goodness or joy worth having.

Chapter 4 - The Perfect Penitent

In making a distinction between the reality of atonement and the theories, I think Lewis is entirely correct to a point. Undoubtedly, one need not be able to explain how Jesus saves you from your sin in order to believe that he does and benefit from it. On the other hand, it seems like there is a lot more scriptural witness to the atonement than what he waves off as “theories that you can take or leave.” Overall, I was pretty underwhelmed with his account of the glorious reconciliation thatr has been achieved for us in Christ.

God became man to turn creatures into sons: not simply to produce better men of the old kind but to produce a new kind of man.

Chapter 5 - Practical Conclusion

Through the means of faith, baptism, and the Lord’s Supper, Christ’s life is communicated to use and Christ himself lives in us and through us. Our good deeds are actually his good deeds carried out in us. Lewis declines to offer any explanation of why or how here, other than it does, and we must take it on authority, which is not unreasonable since so much else of life (science, history, etc.) is taken on authority.

He touches briefly on the question of whether those who never heard of Christ can be saved by Christ, and leaves the door open for it (although is much more affirmative in later chapters). He then offers an answer to the objection as to why God would do it this way rather than come in force to destroy the realm of Satan - namely, to allow us the opportunity to freely choose him, since when he does come in force, there will be no more free choice. It’s probably reading too much into Lewis’s intent, but I can’t help but see here a semi-Pelagian (at least) conception of conversion, where the unbeliever is completely neutral (rather than enslaved to sin) and free to choose God over sin without regenerating work of the Holy Spirit through the gospel.

The Christian does not think God will love us because we are good, but that God will make us good because He loves us.

Book III

Chapter 1 - Morality

Three dimensions to morality: 1) The social - how we interact with one another, and the societal rules and structures that uphold it. 2) The individual - how an individual lives there personal existence. 3) The teleological - what are we here for? What is the purpose of a human? To what end should we strive? Most people tend to get stuck in #1 without acknowledging that it requires moral individuals to ever come close to achieving a stable and sound society. And at the individual level the question hinges on what is right, good, proper working design; in order words, what is humanity for? The different religions have different answers to that question which drive their particular morality.

The moral law is not any one instinct or set of instincts: it is something which makes a kind of tune (the tune we call goodness or right conduct) by directing the instincts.

Chapter 2 - The Cardinal Virtues

Considering the four cardinal virtues of the ancients:

  • Prudence - acting wisely and intelligently. God does not like intellectual slackers any more than other slackers.
  • Temperance - not abstaining from pleasures, but being able to enjoy in the right amounts and abstain when needed.
  • Justice - Balanced scales, honest, being “fair” and judicious
  • Fortitude - Being courageous These are characteristics that a Christian should be identified with as a way of life, not merely acting in some of them every now and then.

Courage is not simply one of the virtues, but the form of every virtue at the testing point.

Chapter 3 - Social Morality

Christian morality is really just saying the same thing we’ve all known deep down - do unto others as you’d have done unto you. Is that really accurate, though? Or does it assume inherited worldview of the Judeo-Christian West? Undoubtedly, there are commonalities, but it seems starkly different than any other society. So maybe the point is arguing that our consciences tell us this.

He goes on to argue that there is no cross-time-and-place application of it , but that it must be worked out by Christians in context. Not by the clergy, but by the ones in the thick of it. The Christian way of economics should be figured out by Christian economists, and so on.

From the New Testament hints, there are some things we can glean - it will tend to be left-leaning with respect to public policy, and conservative with respect to family and personal lifestyles. He goes on to draw specific application in the realm of a debt-driven economy and charitable giving.

Do not waste time bothering whether you ‘love’ your neighbor; act as if you did.

Chapter 4 - Morality and Psychoanalysis

Discussion of the role of psychotherapy and Christian morality. In Lewis’ view, the two are complementary, with psychology addressing the raw material out of which a man makes moral choices while Christian morality is the moral choice itself. The rest of the chapter feels a little too semi-Pelagian (although see Chapter 11), but there is a great point at the end about how every moral choice we make, good or bad, shapes us further into a heavenly character or a hellish character.

Psychoanalysis itself, apart from all the philosophical implications of its Freudian origins, is not in the least contradictory to Christianity.

Chapter 5 - Sexual Morality

Lewis distinguishes between chastity and propriety, the latter changing with the expectations of society and the former fixed for all time. Christian chastity entails sex within the bounds of faithful marriage or none at all. He then answers objections about the source of sexual imbalance not being deprivation, whether there is danger of repression, and finally of God’s grace in the midst of our imperfect obedience. Christians are not opposed to sex and pleasure, but only to the distortions and peddling of it that is so rampant in our day.

Chastity is the most unpopular of the Christian virtues. There is no getting away from it; the Christian rule is, ‘Either marriage, with complete faithfulness to your partner, or else total abstinence.’

Chapter 6 - Christian Marriage

A good discussion of marriage from the unmarried Lewis. Some interesting points:

  • The lifelong nature of marriage is a matter of justice and basic honesty, fulfilling the vows that were made in the height of “being in love.” The feeling often serves to incite the vows.
  • Distinguishing the feeling of being in love from the true and proper grounds of a lasting marriage, which is no less love but one of commitment.
  • Lewis sees an important distinction between Christian marriage and marriage in broader society, arguing that Christians should not force their views of marriage upon non-Christians. He concludes with a traditional defense of the husband’s headship in marriage.

What we call ‘being in love’ is a glorious state, and, in several ways, good for your soul. But it is not the essence of marital love; it does not lead to the permanent and far more satisfying life of marriage.

Chapter 7 - Forgiveness

Forgiveness, says Lewis, may be an even harder thing to live by than chastity, but it is fundamental to loving our neighbors, which includes our enemies. Forgiveness doesn’t mean you must like the other person, or consider them nice, the main thing is that you should resist the inner pull to hatred, which is fundamentally hellish and unhuman. Hate evil, punish and even kill if needed, but keep your heart from hatred.

To be a Christian means to forgive the inexcusable because God has forgiven the inexcusable in you.

Chapter 8 - The Great Sin

The chief of sins, which no non-Christian wants to acknowledge but which they despise in everyone else is Pride. As Lewis calls it, “the complete anti-God state of mind.” This is at the root of so many other vices and through competition is able to make even virtues into terrible sins. It is the devil’s favorite and so deceptive that even attempts at holiness can actually be exhibitions of terrible pride. Not to be confused with appreciating praise from others or admiring someone else.

Pride leads to every other vice: it is the complete anti-God state of mind.

Chapter 9 - Charity

Christian charity, which encompasses much more than the “alms” the word has come to mean, is the disposition of will that seeks to act in love towards the person loved. It is not a “liking” or “affection,” although very frequently the best way to cultivate that affection is by acting in love.

Charity means ‘Love, in the Christian sense’. But love, in the Christian sense, does not mean an emotion. It is a state not of the feelings but of the will; that state of the will which we have naturally about ourselves, and must learn to have about other people.

Chapter 10 - Hope

If you look at history, you find that it is those who are most heavenly minded who have done the most earthly good. Pursue the earthly good first, and you fall short. Many of our desires are found to unfillable in this life, which gives us indication that maybe we were made for a different world. The Christian does not naively keep chasing the satisfaction that never comes, nor does he settle into cynicism, but instead receives the temporal as a blessing and foretaste of the eternal that only God can supply.

If you read history you will find that the Christians who did most for the present world were precisely those who thought most of the next.

Chapter 11 - Faith

The first of two meanings of faith - simply belief, regarding Christianity as true. The reasoning may be compelling but we’re often tempted to unbelief by emotion and not reason. This kind of faith persists in belief that what you know is true in the face of temptations from emotion, etc.

With respect to faith in the second sense, it’s important to realize that we can never please God of our own will, and all the good we do is actually enabled by his gift.

Faith, in the sense in which I am here using the word, is the art of holding on to things your reason has once accepted, in spite of your changing moods.

Chapter 12 - Faith

Faith in the second sense is fundamentally an act of trust. Trust in Christ as the one who is perfect, and who shares his perfection with us, so that though we have reached the end of our rope trying to walk in obedience, and realized we fell short of it, we can trust that he will yet deliver us. This is a personal allegiance to the kind, and it follows that those with such allegiance will also seek to align their lives with the king’s will.

Faith…is the art of holding on to things your reason has once accepted, in spite of your changing moods.

Book 4

Chapter 1 - Making and Begetting

Lewis makes a defense of theology, agreeing that the map is not the territory but that the map is absolutely essential to getting along in life. Theology is practical, both in helping us engage the ideas of the world as well as knowing what our end will be and what we should be about. For Lewis, the significance is the transition from animal life (Bios) to Spiritual life (Zoe). We shall be sons of God in a sense not true today.

We don’t use the words ‘begotten’ or ‘begetting’ much in modern English, but everyone still knows what they mean. To beget is to become the father of: to create is to make. And the difference is this. When you beget, you beget something of the same kind as yourself. A man begets human babies, a beaver begets little beavers, and a bird begets eggs that turn into baby birds. But when you make, you make something of a different kind from yourself.

Chapter 2 - The Three Personal God

God is not personal, but super-personal. Similar to one dimensional vs three dimensional, God is three personality in one being. The illustration of the Trinity at work in prayer is helpful. He also makes an important point that you cannot hope to know God without his first making himself know. The simplicity of some religions is their give away that they are made up.

God is not a static thing…not even a person…but a dynamic, pulsating activity, a life, almost a kind of drama. Almost, if you will not think me irreverent, a kind of dance.

Chapter 3 - Time and Beyond Time

A fairly philosophical chapter about God being above time, so that he experiences all moments as real and present. What is past or future to us is no less present to him. This is how Lewis accounts for God’s ability to answer the prayers of thousands at the same time. It is very speculative to be sure, but helps Lewis with the question of foreknowledge.

If you picture Time as a straight line along which we have to travel, then you must picture God as the whole page on which the line is drawn. We come to points on the line one by one: we have to leave A behind before we get to B, and cannot reach C until we leave B behind. God, from above or outside or all round, contains the whole line, and sees it all.

Chapter 4 - Good infection

The Father and Son have always existed in a love relationship in which the father begets the Son, who is his Word and Speech. The union of love between them is also a person, the Holy Spirit. There is a dance between them are we are invited to join in and share in the life-giving, loving energy that they share.

The whole purpose for which we exist is to be taken into the life of God. Wrong ideas about what we are up to lead to wrong ideas about Christianity… What we are trying to do is to remain fully human, all the while trying to become taken up into God, or recreated into Christ-likeness.

Chapter 5 - The obstinate toy soldiers

Christ’s incarnation was for the purpose of uniting humanity with the divine spiritual life. Humanity is not a bunch of isolated entities but truly a united organism when viewed over time. Since the natural in us has come to be opposed to the spiritual, Christ’s incarnation is also for the purposes of killing the natural.

The Son of God became a man to enable men to become sons of God.

Chapter 6 - Two Notes

1) The idea of multiple begotten Sons of God seems non-sensical 2) Human race as an organism does not deny the individual. The two extreme mistakes are Individualism on one side and Collectivism on the other.

Christianity thinks of human individuals not as mere members of a group or items in a list, but as organs in a body—different from one another and each contributing what no other could.

Chapter 7 - Let’s Pretend

When we begin to “play Christ,” knowing that he is with us and working in us, we are gradually transformed into the real thing. When we pray, the living Christ is at work beside us. As the transformation happens our awareness of our own sinfulness goes deeper than our actions but we realize the kind of person we are, our default responses are corrupt.

Very often the only way to get a quality in reality is to start behaving as if you had it already. That is why children’s games are so important. They are always pretending to be grown-ups—playing soldiers, playing shop. But all the time, they are hardening their muscles and sharpening their wits so that the pretence of being grown-up helps them to grow up in earnest.

Chapter 8 - Is Christianity hard or easy

It’s hard, but is much easier than the lazy way. Christianity consists in becoming sons of God, and looking like Christ. It is not a matter of doing the good things and not doing the bad things. We are called to give our full selves over to Christ, but instead we choose the impossible task of obeying Christ while trying to hold onto the world.

The Christian way is different: harder, and easier. Christ says ‘Give me All. I don’t want so much of your time and so much of your money and so much of your work: I want You.’

Chapter 9 - Counting the cost

Many people come to Christ seeking help for one vice that’s troubling them, but Christ does not transform us only one way. Once he gets started, he’s going for the full transform. WE don’t yet know the full depth of what we will be but it will be glorious. All of the trials and challenges we face are shaping us into this.

It would seem that Our Lord finds our desires not too strong, but too weak. We are half-hearted creatures, fooling about with drink and sex and ambition when infinite joy is offered us, like an ignorant child who wants to go on making mud pies in a slum because he cannot imagine what is meant by the offer of a holiday at the sea. We are far too easily pleased.

Chapter 10 - Nice People or New Men

Should the Christian always be nicer than the non-Christian? This is not the right way to look at it. The Christian will always be a better version of the same persona as a non-Christian. A lot of argumentation about the importance of free will and choosing to follow God. We must not confuse natural disposition, which itself is a gift of God, with holiness.

It is not enough to be ‘nice,’ to be merely old Adam dressed up in a new suit of clothes. The New Man in Christ, the new creation, is what matters.

Chapter 11 - The New Man

Christianity as the huge next step in the evolution of man, but not really evolution but a giant leap, and completely unlike evolution in that it’s by the will of the person being changed. During this transformation, we become more ourselves than we’ve ever been.

To become new men means losing what we now call ‘ourselves.’ Out of ourselves, into Christ, we must go.