Our present secular culture has fixed a great gap between people of my generation (i.e. those from the Jurassic period) and modern young people. And this gap is most easily observed when looking at our divergent understandings of fornication. Indeed, I remember once giving instruction to a young (chaste) catechumen, and casually mentioning that the Church opposed fornication. The eyes of the young’un glazed over a bit before asking me what fornication was. The person wasn’t asking for a more precise definition; rather, the person had no idea what the word meant. The word had effectively vanished from modern vocabulary and could only be recovered by looking it up in the Oxford English Dictionary. The current phrase used to describe the practice is, I am told, “hooking up”.

So, the question remains, “Why does the Church oppose ‘hooking up’?” Why does the Church insist that sexual congress (I told you I was from the Jurassic period) be reserved exclusively to married couples? What’s the problem with having sex with someone to whom you are not married and have no intention of marrying?

It will not do to simply quote Scripture, for its authority has long since ceased to function effectively as far as our secular culture is concerned. If things in Scripture (like the commandments, “Love your neighbour” or “Take care of the poor”) find an echo and confirmation in secular culture, that is fine—and entirely coincidental. But Scripture can no longer function to inform or correct our secular culture, and people who quote Scripture to worldlings as if the Scriptures were an effective authority are simply wasting their breath and blowing their credibility. If I were to respond to the question “Why should I not hook up?”, by saying “You should not ‘hook up’ because Scripture forbids it”, they would simply respond in turn, “Why on earth does it forbid it?” Young people are looking for inner rationale, and for a real and sensible reason, not for proof-texts. And, given our present culture, they have a point.

The answer is: the Church forbids fornication because fornication gets in the way of one of the main purposes of authentic human sexuality. It frustrates the first intended goal of sex, and is a dilution of it. I deliberately use the phrase, “authentic human sexuality” to differentiate it from animal sexuality. Obviously, “hooking up” presents no moral problems for animals. Cats and dogs regularly “hook up”, and that is pretty much the beginning and end of it. All things being equal, lots of feline and canine hooking up produces lots of kittens and puppies, but apart from the release of the moment and the eventual birth of offspring, nothing more is involved. Cats and dogs do not feel the necessity to exchange phone numbers afterward, or to call in a few days to see how the other is doing. There is no emotional baggage, and no psychological or spiritual connection. In other words, there is no possibility for love, self-transcendence, sacrifice, or growth. After the moment is concluded, Fido and Mitzi go their separate ways, and that’s about it.

Looking at the (limited) components of animal sexuality (or “mating”, as most people call it), gives us an opportunity to better understand the components and possibilities and goals of authentic human sexuality. The tragedy and glory of being human, of course, is that nothing is automatic with us, as it mostly is for the animals. We are not compelled by our human natures to grow, or to become holy, or even to become nice. We can become self-sacrificing and loving, or we can refuse. We can use our sexuality as a vehicle to grow in authenticity, or we can choose otherwise. Animals have no choice. Moral choice (and with it, the possibility of sin) is peculiar to humanity. We can treat our sexuality as a part of what separates us from the animal kingdom, or we can simply “hook up”. But God invented sex as a pathway to human growth, and merely hooking up does not set us upon this path to authenticity. (People tend to forget that the Church teaches that God is the One who invented sex, and that He thought it was a good idea. Read Genesis, and the Song of Solomon.)

The reality is that sex involves what was once called “becoming one flesh”. This mingling occurs whether one is married or not, and whether one intends it or not. Presumably those deciding to casually hook up have no intention of becoming one flesh with the partner, or of having any real long-term relationship. But becoming one flesh (or “one organism”, to use more modern language) occurs anyway, even if the hooking up is simply with a paid prostitute. St. Paul informs us that this is the case in 1 Cor. 6:16: “Do you not know that the one who joins himself to a prostitute [Greek pornē] becomes one body with her? For He says, ‘The two will become one flesh’.” One can deny St. Paul’s assertion all one likes, but the heart and the emotions know differently. “Casual sex” is a contradiction in terms. All sexual union involves opening up parts of one’s innermost self to another at a tremendously intimate and vulnerable level. That is why one instinctively seeks to “get a room” for privacy. That is why one feels the obligation afterward to say, “I’ll call you”, even when there is no real intention of doing so. Our secular culture does its best to deny this, and bombards us with movies, celebrity examples, books, and magazines which insist that casual sex is possible, and that no such inner connections are established by the sexual act. The secret inner history of young people, however, tells a different story, one of heartbreak, misunderstanding, and longing. In this as in so many other areas, our secular culture is lying. Any sexual act unites on a basic and lasting level.

As said above, nothing is automatic for human beings. The sexual act establishes an inner emotional connection with the partner, but one is not forced to nurture it. One can choose to instantly sever the connection, to pretend that it was never established and does not exist, and so to go cheerfully from partner to partner. But there is a cost attached to such pretending, and by this I do not refer to the possibility of unwanted pregnancy or sexually-transmitted disease, though these should not be discounted. I refer to the secret cost to the inner ability to make connections, to the creeping insensibility to the other, and the denied possibilities for growth. When it is used the way God intended, repeated sexual union opens up the possibility of mutual long-term enrichment. By having sex with one’s marital partner, one has the possibility of investing in the other person, so that each is strengthened by the other, moulded by the other, given deeper identity by the other. Of course this is not automatic, and can be thwarted by selfishness and sin. But the possibility remains, and this is the goal of sexual union. (Having children is of course another goal, but I am speaking now merely the unitive power of sexuality, not its ultimate fruitfulness in creating other persons.) Even our culture recognizes this to some degree, in its fascination for couples who have been married to each other for many years and retain their love for each other.

Casual sex, therefore, involves sundering the act from the relationship and from love. Love is almost completely misunderstood in our culture. We define it as a feeling, an emotion, and speak of infatuation as “being in love”. In fact, love is not an emotion, but an action. We love the other not by feeling strong emotions of attachment, delight and infatuation (lovely as these emotions are), but by serving them and meeting their needs. If we love someone, we refuse to abandon them, but will stay with them despite the cost. This is the definition of marriage—to commit oneself to another in service and self-sacrifice, “for better or for worse, in sickness and in health, for richer or for poorer”. This commitment provides the framework and the possibility for love to endure. Love says, “Even if you become old, and sick, and wrinkled, and poor, I will not abandon you. Nothing but death will drive me from your side.” Since we may become poor, and certainly will become old and sick and wrinkled, this assurance and the promise are necessary if love is to endure. Sex is meant to serve this love, and to bring the two lovers closer in a continually-reinforced emotional bond. That is why the Church insists that sex be reserved for marriage, for sex was created to lead the couple to this lasting fulfillment. Fornication short-circuits the real purpose of sex.

One last word about sex: the center of Christian morality is not here. Fornication is a sin, since it takes sexuality and wastes it on lesser things, and lessens our capacity for lasting joy. (That is partly what St. Paul means when he says in 1 Cor. 6:18 that the fornicator sins against his own body.) But there are worse sins than the sexual ones, and these involve the spirit and its temptations to pride more than they involve the body. To quote C.S. Lewis, “a cold, self-righteous prig who goes regularly to church may be far nearer to hell than a prostitute. But of course,” he says, “it is better to be neither.”