The Christian attitude toward sex is popularly thought to be the Platonist view, but most definitely it is not. It differs quite radically from each of these three prominent views.
Contrary to the Platonist view, the Bible teaches that sex is very good (Gen. 1:31). God would not create and command something to be done in marriage (1 Cor. 7:3–5) that was not good. The Song of Solomon is filled with barefaced rejoicing in sexual pleasure. In fact, the Bible can be very uncomfortable for the prudish.
Contrary to the realist ‘sex-as-appetite’ view, the Bible teaches that sexual desires are broken and usually idolatrous. All by themselves, sexual appetites are not a safe guide, and we are instructed to flee our lusts (1 Cor. 6:18). Our sexual appetite does not operate the same as our other appetites. To illustrate this point, C. S. Lewis asks us to imagine a planet where people pay money to watch someone eat a mutton chop, where people ogle magazine pictures of food. If we landed on such a planet, we would think that the appetite of these people was seriously deranged. Yet that is just how modern people approach sex.
Contrary to the romantic view, the Bible teaches that love and sex are not primary for individual happiness. What the Bible says about sex and marriage ‘has a singularly foreign sound for those of us brought up on romantic notions of marriage and sex. We are struck by the stark realism of the Pauline recommendations in 1 Corinthians 7 . . . but [most of all by] the early church’s legitimation of singleness as a form of life [which] symbolized the necessity of the church to grow through witness and conversion.’
The Bible views sex not primarily as self-fulfillment but as a way to know Christ and build his kingdom. That view undercuts both the traditional society’s idolatry of sex-for-social-standing and the secular society’s idolatry of sex-for-personal-fulfillment.
– Tim Keller