Very wise words by Lewis on the place of emotion:
Because C. S. Lewis was such a deep thinker and so widely read, he was able to offer incisive and wise words about all sorts of things, including those things he may not have yet experienced. Thus he could offer us sage advice on things like marriage and sexuality, even decades before he was married.
He also could tell us great truths about emotion, and how we must guard against being guided by feelings alone. Faith may well incorporate emotion, but it is not limited to nor defined by it. He wrote often about this matter, but here I want to just quote from one of his books: Mere Christianity.
Let’s start with his chapter on Christian marriage:
The idea that “being in love” is the only reason for remaining married really leaves no room for marriage as a contract or promise at all. If love is the whole thing, then the promise can add nothing? and if it adds nothing, then it should not be made. The curious thing is that lovers themselves, while they remain really in love, know this better than those who talk about love. As Chesterton pointed out, those who are in love have a natural inclination to bind themselves by promises. Love songs all over the world are full of vows of eternal constancy. The Christian law is not forcing upon the passion of love something which is foreign to that passion’s own nature: it is demanding that lovers should take seriously something which their passion of itself impels them to do.
And, of course, the promise, made when I am in love and because I am in love, to be true to the beloved as long as I live, commits me to being true even if I cease to be in love. A promise must be about things that I can do, about actions: no one can promise to go on feeling in a certain way. He might as well promise never to have a headache or always to feel hungry….
What we call “being in love” is a glorious state, and, in several ways, good for us. It helps to make us generous and courageous, it opens our eyes not only to the beauty of the beloved but to all beauty, and it subordinates (especially at first) our merely animal sexuality; in that sense, love is the great conqueror of lust. No one in his senses would deny that being in love is far better than either common sensuality or cold self-centredness. But, as I said before, “the most dangerous thing you can do is to take any one impulse of our own nature and set it up as the thing you ought to follow at all costs.” Being in love is a good thing, but it is not the best thing. There are many things below it, but there are also things above it. You cannot make it the basis of a whole life. It is a noble feeling, but it is still a feeling. Now no feeling can be relied on to last in its full intensity, or even to last at all. Knowledge can last, principles can last, habits can last, but feelings come and go. And in fact, whatever people say, the state called “being in love” usually does not last. If the old fairy-tale ending “They lived happily ever after” is taken to mean “They felt for the next fifty years exactly as they felt the day before they were married,” then it says what probably never was nor ever could be true, and would be highly undesirable if it were. Who could bear to live in that excitement for even five years? What would become of your work, your appetite, your sleep, your friendships? But, of course, ceasing to be “in love” need not mean ceasing to love. Love in this second sense – love as distinct from “being in love” is not merely a feeling. It is a deep unity, maintained by the will and deliberately strengthened by habit; reinforced by (in Christian marriages) the grace which both parents ask, and receive, from God. They can have this love for each other even at those moments when they do not like each other; as you love yourself even when you do not like yourself. They can retain this love even when each would easily, if they allowed themselves, be “in love” with someone else. “Being in love” first moved them to promise fidelity: this quieter love enables them to keep the promise. It is on this love that the engine of marriage is run: being in love was the explosion that started it.
And in his chapter on forgiveness he says this:
We might try to understand exactly what loving your neighbour as yourself means. I have to love him as I love myself. Well, how exactly do I love myself?
Now that I come to think of it, I have not exactly got a feeling of fondness or affection for myself, and I do not even always enjoy my own society. So apparently “Love your neighbour” does not mean “feel fond of him” or “find him attractive”. I ought to have seen that before, because, of course, you cannot feel fond of a person by trying. Do I think well of myself, think myself a nice chap? Well, I am afraid I sometimes do (and those are, no doubt, my worst moments) but that is not why I love myself. In fact it is the other way round: my self-love makes me think myself nice, but thinking myself nice is not why I love myself. So loving my enemies does not apparently mean thinking them nice either. That is an enormous relief. For a good many people imagine that forgiving your enemies means making out that they are really not such bad fellows after all, when it is quite plain that they are. Go a step further. In my most clear-sighted moments not only do I not think myself a nice man, but I know that I am a very nasty one. I can look at some of the things I have done with horror and loathing. So apparently I am allowed to loathe and hate some of the things my enemies do. Now that I come to think of it, I remember Christian teachers telling me long ago that I must hate a bad man’s actions, but not hate the bad man: or, as they would say, hate the sin but not the sinner.
For a long time I used to think this a silly, straw-splitting distinction: how could you hate what a man did and not hate the man? But years later it occurred to me that there was one man to whom I had been doing this all my life – namely myself. However much I might dislike my own cowardice or conceit or greed, I went on loving myself. There had never been the slightest difficulty about it. In fact the very reason why I hated the things was that I loved the man. Just because I loved myself, I was sorry to find that I was the sort of man who did those things. Consequently, Christianity does not want us to reduce by one atom the hatred we feel for cruelty and treachery. We ought to hate them. Not one word of what we have said about them needs to be unsaid. But it does want us to hate them in the same way in which we hate things in ourselves: being sorry that the man should have done such things, and hoping, if it is anyway possible, that somehow, sometime, somewhere he can be cured and made human again.
This from his chapter on charity (love):
But though natural likings should normally be encouraged, it would be quite wrong to think that the way to become charitable is to sit trying to manufacture affectionate feelings. Some people are “cold” by temperament; that may be a misfortune for them, but it is no more a sin than having bad digestion is a sin; and it does not cut them out from the chance, or excuse them from the duty, of learning charity. The rule for all of us is perfectly simple. Do not waste time bothering whether you “love” your neighbour; 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. If you injure someone you dislike, you will find yourself disliking him more. If you do him a good turn, you will find yourself disliking him less. There is, indeed, one exception. If you do him a good turn, not to please God and obey the law of charity, but to show him what a fine forgiving chap you are, and to put him in your debt, and then sit down to wait for his “gratitude” you will probably be disappointed. (People are not fools: they have a very quick eye for anything like showing off, or patronage.) But whenever we do good to another self, just because it is a self, made (like us) by God, and desiring its own happiness as we desire ours, we shall have learned to love it a little more, or, at least, to dislike it less.
Consequently, though Christian charity sounds a very cold thing to people whose heads are full of sentimentality, and though it is quite distinct from affection, yet it leads to affection. The difference between a Christian and a worldly man is not that the worldly man has only affections or “likings” and the Christian has only “charity.” The worldly man treats certain people kindly because he “likes” them: the Christian, trying to treat everyone kindly, finds himself liking more and more people as he goes on—including people he could not even have imagined himself liking at the beginning….
Good and evil both increase at compound interest. That is why the little decisions you and I make every day are of such infinite importance. The smallest good act today is the capture of a strategic point from which, a few months later, you may be able to go on to victories you never dreamed of. An apparently trivial indulgence in lust or anger today is the loss of a ridge or railway line or bridgehead from which the enemy may launch an attack otherwise impossible.
Lastly, some thoughts from his chapter on faith:
Now Faith, in the sense in which I am here using the word, is the art of holding onto things your reason has once accepted, in spite of your changing moods. For moods will change, whatever view your reason takes. I know that by experience. Now that I am a Christian, I do have moods in which the whole thing looks very improbable; but when I was an atheist, I had moods in which Christianity looked terribly probable. This rebellion of your moods against your real self is going to come anyway. That is why Faith is such a necessary virtue; unless you teach your moods “where they get off” you can never be either a sound Christian or even a sound atheist, but just a creature dithering to and fro, with its beliefs really dependent on the weather and the state of its digestion. Consequently one must train the habit of Faith.
The first step is to recognize the fact that your moods change. The next is to make sure that, if you have once accepted Christianity, then some of its main doctrines shall be deliberately held before your mind for some time every day. That is why daily prayers and religious reading and church going are necessary parts of the Christian life. We have to be continually reminded of what we believe. Neither this belief nor any other will automatically remain alive in the mind. It must be fed. And as a matter of fact, if you examined a hundred people who had lost their faith in Christianity, I wonder how many of them would turn out to have been reasoned out of it by honest argument? Do not most people simply drift away?