The Law of Undulation

This is chapter 8 of the Screwtape Letters. It has been called the Law of Undulation.

For those who don’t know, Screwtape is a demon writing to an apprentice demon named Wormwood. Thus, all that is said is said from the perspective of the demon. When you hear about the Enemy, it means God.

So you “have great hopes that the patient’s religious phase is dying away”, have you? I always thought the Training College had gone to pieces since they put old Slubgob at the head of it, and now I am sure. Has no one ever told you about the law of Undulation?

Humans are amphibians—half spirit and half animal. (The Enemy’s determination to produce such a revolting hybrid was one of the things that determined Our Father to withdraw his support from Him.) As spirits they belong to the eternal world, but as animals they inhabit time. This means that while their spirit can be directed to an eternal object, their bodies, passions, and imaginations are in continual change, for to be in time means to change. Their nearest approach to constancy, therefore, is undulation—the repeated return to a level from which they repeatedly fall back, a series of troughs and peaks. If you had watched your patient carefully you would have seen this undulation in every department of his life—his interest in his work, his affection for his friends, his physical appetites, all go up and down. As long as he lives on earth periods of emotional and bodily richness and liveliness will alternate with periods of numbness and poverty. The dryness and dulness through which your patient is now going are not, as you fondly suppose, your workmanship; they are merely a natural phenomenon which will do us no good unless you make a good use of it.

To decide what the best use of it is, you must ask what use the Enemy wants to make of it, and then do the opposite. Now it may surprise you to learn that in His efforts to get permanent possession of a soul, He relies on the troughs even more than on the peaks; some of His special favourites have gone through longer and deeper troughs than anyone else. The reason is this. To us a human is primarily good; our aim is the absorption of its will into ours, the increase of our own area of selfhood at its expense. But the obedience which the Enemy demands of men is quite a different thing. One must face the fact that all the talk about His love for men, and His service being perfect freedom, is not (as one would gladly believe) mere propaganda, but an appalling truth. He really does want to fill the universe with a lot of loathsome little replicas of Himself—creatures, whose life, on its miniature scale, will be qualitatively like His own, not because He has absorbed them but because their wills freely conform to His. We want cattle who can finally become food; He wants servants who can finally become sons. We want to suck in, He wants to give out. We are empty and would be filled; He is full and flows over. Our war aim is a world in which Our Father Below has drawn all other beings into himself: the Enemy wants a world full of beings united to Him but still distinct.

And that is where the troughs come in. You must have often wondered why the Enemy does not make more use of His power to be sensibly present to human souls in any degree He chooses and at any moment. But you now see that the Irresistible and the Indisputable are the two weapons which the very nature of His scheme forbids Him to use. Merely to over-ride a human will (as His felt presence in any but the faintest and most mitigated degree would certainly do) would be for Him useless. He cannot ravish. He can only woo. For His ignoble idea is to eat the cake and have it; the creatures are to be one with Him, but yet themselves; merely to cancel them, or assimilate them, will not serve. He is prepared to do a little overriding at the beginning. He will set them off with communications of His presence which, though faint, seem great to them, with emotional sweetness, and easy conquest over temptation. But He never allows this state of affairs to last long. Sooner or later He withdraws, if not in fact, at least from their conscious experience, all those supports and incentives. He leaves the creature to stand up on its own legs—to carry out from the will alone duties which have lost all relish. It is during such trough periods, much more than during the peak periods, that it is growing into the sort of creature He wants it to be. Hence the prayers offered in the state of dryness are those which please Him best. We can drag our patients along by continual tempting, because we design them only for the table, and the more their will is interfered with the better. He cannot “tempt” to virtue as we do to vice. He wants them to learn to walk and must therefore take away His hand; and if only the will to walk is really there He is pleased even with their stumbles. Do not be deceived, Wormwood. Our cause is never more in danger, than when a human, no longer desiring, but intending, to do our Enemy’s will, looks round upon a universe from which every trace of Him seems to have vanished, and asks why he has been forsaken, and still obeys.

But of course the troughs afford opportunities to our side also. Next week I will give you some hints on how to exploit them,

Your affectionate uncle

This is one of my favorite passages in all of C.S. Lewis, particularly the last big paragraph. Why?

Because we all know these troughs. We also know the peaks. When the peaks come, we realize the troughs were nothing. When we get to the troughs though, we forget all that we learned in the peaks.

There are times I have woke up angry with God for something. Things just aren’t going well in life. However, those times, I still serve. I sometimes wonder why, but it is just so built into me that I do so. I remember someone saying in a sermon once about the times that we say “Lord, I’m so angry now, but I love you anyway!”

I can relate.

I then take heart at what Greg Koukl says about this passage. The Christian who serves now is the Christian who can’t be defeated. Why? Because it’s not entirely dependent on emotions. It’s a commitment of the mind and will.

Well readers, I know it’s short, but I’ve had a late evening and I wanted to say something and this had been on my mind. If you are in the peak, be thankful. If in the trough, (Which is where I tend to live) remember that this too will pass.



12 Responses to “The Law of Undulation”

  1. Steven Carr Says:

    ‘ He really does want to fill the universe with a lot of loathsome little replicas of Himself’

    Genesis 3:22 And the LORD God said, “The man has now become like one of us, knowing good and evil.

    Lewis is right on the money again.

    He said that God wants us to become replicas of him, and Genesis points out where God is delighted that Adam and Eve have become like him.

  2. JenSen Says:

    The Screwtape Letters is one of my favourite books. I love Lewis’ thought process through the whole thing, and I’ve recently re-read the book in the last week (this makes over a dozen times it’s been read here now). To see this here was great.

  3. Derek Says:

    That last sentence of the last main paragraph is my all-time favorite Screwtape Letters quote.

  4. JenSen Says:

    Derek, I love that one too.

  5. FeniXpirit Says:

    I, too, adore this book generally, and Letter 8 specifically. I discovered it 15 or so years ago, and both suffering with and recovering from bipolar disorder often finds me seeking this brilliant description, particularly the last paragraph, of my internal experience. When I am so often paralyzed by the darkness in my soul, it is a comfort to know that to continue to walk, to stumble, to crawl — obediently– is what matters, not how far I am able to get.

    Thanks all!

    • Wayne Says:

      FeniXpirit, I really liked your comment, makes me feel better about my own temptations and failures. And like you all, I too adore this literary diamond.

  6. Besspher Says:

    I must say chapter 8 is my favorite because the last paragraph encourages me that although ‘WE’ are trying ad we happen to make a mistake, God is not mad at ‘US’ because He knows our heart:

    This is what I wrote in my book:
    “God wants us to walk; Like a father, He does not want us in the same crawling state. He wants us to learn to walk, and in doing that we will fall, but God (our father) is always there to pick us up. He is pleased with our stumble if only our will is to walk… Walk in Christ.

  7. The First Time… Again… « More Than J Says:

    […] You can read the whole chapter by clicking here. […]

  8. T Says:

    Although C.S. Lewis is a great writer, I must say all the credit goes to his Creator.

    Certainly it is a entertainment of reading with God’s laws throughout.

    Many non-believers are attracted to these writings and by no mistake, they speak to our created innate design by God.

    Remember, C.S. Lewis has nothing over God. All those ideas come from God, they are not his ideas.

    I think if I were to write a comment about the letters, I simply would say, it’s all in God’s word and the value would be small compared to reading God’s mind, from the Bible.

  9. Justin Says:

    Read SL years ago, and every few months my mind will come back to this idea, though I had called it by the wrong name (induration/indulation) and had a vague understanding of it (I thought it was merely the state of being IN time). Was doing a text search of Mere Christianity and SL today and couldn’t find my two forms of the word in either one, finally google searched it and, eventually, found this. Thanks.

  10. Mary Iskandar Says:


  11. Lightning Round – 2013/11/27 | Free Northerner Says:

    […] Lewis described this process as undulation. […]

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: