In his celebrated work Mere Christianity, C.S. Lewis invites us to imagine a world where people crowded into adult theaters and strip clubs not to see a girl undress, but to see someone “bringing a covered plate on to the stage and then slowly lifting the cover so as to let everyone see…that it contained a mutton chop or a bit of bacon.”
“Would you not think that in that country something had gone wrong with the appetite for food? And would not anyone who had grown up in a different world think there was something equallyabout the state of the sex instinct among us? One critic said that if he found a country in which such striptease acts with food were popular, he would conclude that the people of that country were starving….[But] ‘starvation’ [is not the only explanation] we can imagine. Everyone knows that the sexual appetite, like our other appetites, grows by indulgence. Starving men may think much about food, but so do gluttons; the gorged, as well as the famished, like titillations.”
But perhaps the issue is that we’re starving for something more than sex can ever offer. The twentieth century novelist Kurt Vonnegut suggests something like this in his obscure novel Breakfast of Champions. In his novel we meet Kilgore Trout, a science fiction writer whose curse is that he can only get published in pornographic magazines. In one of Trout’s stories, an “earthling” finds himself “on a planet where all animal and plant life had been killed by pollution, except for [the aliens.] The [aliens] ate food made from petroleum and coal.”
“They asked [the astronaut] if dirty movies were a problem on Earth, too, and [he] said, “Yes.” They asked him if the movies were really dirty, and [he] replied, “As dirty as movies could get.” This was a challenge to the humanoids, who were sure then: dirty movies could be at anything on Earth. So …they floated to a dirty movie house downtown….[T]he main feature…was about a male and a female and their two children, and their dog and their cat. They ate steadily for an hour and a half—soup, meat, biscuits, butter, vegetables, mashed potatoes and gravy, fruit, candy, cake, pie. … After a while, the actors couldn’t eat any more….They cleared the table slowly. They went waddling out into the kitchen, and they dumped about thirty pounds of leftovers into a garbage can. The audience went wild.”
Even after leaving the theater, the astronaut and his alien companions were propositioned by prostitutes, who could only offer them artificial versions of real food. But if he took one of them up on her offer, the alien would “talk dirty about how fresh and full of natural juices the food was, even though the food was fake.”
Every major religion contains some moral code concerning sex. Christianity sees sex as a sort of celebration—a gift given from God for his children to enjoy within the context of marriage. King Solomon instructs his readers to “drink water from your own cistern, flowing water from your own well” (Proverbs 5:15). The context, of course, is that we should not look for satisfaction outside the source we find in God’s gift of marriage. For those who are single, this also means not looking for sexual satisfaction outside the boundaries of marriage.
But years after Solomon, God would speak through Jeremiah, saying “My people have forsaken me, the spring of living water, and dug their own cisterns, broken cisterns that cannot hold water” (Jeremiah 2:13). You understand the imagery here, right? It’s like trading the Perrier bottling plant for the sewage treatment facility.
No wonder our sexual appetites have become so broken. Like the characters in Vonnegut’s novel, we are starved for something real and nourishing, so we turn to some fantasy version for our own pleasure. God’s design for sex has been perverted into something that—ultimately—provides no real satisfaction.
THE PURITY MYTH?
One of the myths we must overcome is that Christianity is in some way opposed to sex. Or worse: many would see Christianity’s sexual ethics as in some way unhealthy. In her book The Purity Myth, Jessica Valenti tackles “the dangerous burden that falls on our girls to conform to impossible standards of purity.” Indeed, Christianity’s teachings on sexual purity have alternately been dismissed as laughably impractical, or attacked as dangerously oppressive.
Much of this owes, at least in part, to the fact that Christianity has been willing to lament the violations of God’s design than to celebrate the goodness of God’s design. Most sermons decompose to moralistic commands to “behave yourself,” while Christian dating books read more like guides on what not to do before your honeymoon.
So while we might not dismiss “purity” as merely a “myth,” we might also recognize purity is not the main goal. Purity is certainly not the main goal for human sexuality, and it’s also not the main goal for the Christian life in general. Instead, we make our focus the gospel. The gospel tells us that human beings are flawed and broken in every respect—including our sexuality. But the gospel also promises that we are loved and valued beyond comprehension, and by trusting in Jesus we receive the acceptance of God. This—this—is Christianity’s highest goal: to know God deeply and intimately. Moral purity can never terminate on itself; it must always point us joyfully upward to the face of the Creator.
So how does the gospel help us understand God’s plan for sex? And how can the gospel help us untangle the various ways that sex has become such a “dirty” thing in our culture?
 C.S. Lewis, Mere Christianity
 Kurt Vonnegut, Breakfast of Champions
 Jessica Valenti, The Purity Myth