C.S. Lewis, in his book Mere Christianity, wrote:
The Christian ideal of marriage is based on Christ’s words that a man and wife are to be regarded as a single organism—for that is what the words “one flesh” would be in modern English. And the Christians believe that when He said that he was not expressing a sentiment but stating a fact—just as one is stating a fact when one says that a lock and its key are one mechanism, or that a violin and a bow are one musical instrument. The inventor of the human machine was telling us that its two halves, the male and the female, were made to be combined together in pairs, not simply on the sexual level, but totally combined. The monstrosity of sexual intercourse outside marriage is that those who indulge in it are trying to isolate one kind of union (the sexual) from all the other kinds of union which were intended to go along with it and make up the total union. The Christian attitude doesn’t mean that there is anything wrong about sexual pleasure, any more than about the pleasure of breathing. It means that you mustn’t isolate that pleasure and try to get it by itself, any more than you ought to try to get the pleasures of tasting without swallowing and digesting, by chewing things and spitting them out again.
As a consequence, Christianity teaches that marriage is for life. … Churches all agree with one another about marriage as great deal more than any of them agrees with the outside world. I mean, they all regard divorce as something like cutting up a living body, as a kind of surgical operation. Some of them think the operation so violent that it can’t be done at all; others admit it as a desperate remedy in extreme cases. They are all agreed that it is more like having both legs cut off than it is like dissolving a business partnership or even deserting a regiment. What they all disagree with is the modern view that it is a simple readjustment of partners, to be made whenever people feel they are no longer in love with one another, or when either of them falls in love with someone else.
BTW, when Lewis quotes Jesus’ “one flesh” saying, Jesus himself was quoting Genesis.
A prayer from the Book of Common Prayer (1549): Almighty God, our heavenly Father, you set the solitary in families. We commend to your care all the homes where your people live. Keep them, we pray, free from bitterness, from the thirst for personal victory, and from pride in self. Fill them with faith, virtue, knowledge, moderation, patience, and godliness. Knit together in enduring affection those who have become one in marriage. Let children and parentys have full respect for one another; and light the fire of kindliness among us all, that we may show affection for each other, through Jesus Christ our Lord. Amen.
My source for this post: While I did read Mere Christianity forty-plus years ago, I found this quote and the prayer in For All the Saints, year 1, volume 2, 929-930