Issues in sexual morality have been around for a long time. A cursory reading of the book of Genesis shows that humans have struggled with their sexual impulses and longings since Adam and Eve took matters into their own hands. At one level, the challenges before us today are nothing new.

And yet some things have changed that put issues like premarital sex, pornography, and homosexuality before us more intensely and in new ways. For example, the media and the internet place sexual innuendos, imagery, and explicit sexual immoralities before us in unprecedented ways. We feel more intensely than ever the compulsions and passions of our sexual drive. And beyond that, worldview paradigms about sex are constantly changing.

Dale Kuehne, a professor of politics, argues that what we face are not just changing patterns of sexual ethics, but whole new ways of understanding the human self and human relationships. “Marriage and the extended family were the relational foundation of the tWorld [traditional world over several thousand years]…. The tWorld was constructed on relationships of obligation.” But we now live, says Kuehne, in an iWorld “predicated on a foundational belief that the expansion of individual rights will lead to increased happiness and fulfillment” (Sex and the iWorld: Rethinking Relationship beyond an Age of Individualism [Baker, 2009] 35, 67). With a framework of individual rights linked to personal happiness as the highest good, traditional understandings of sex are challenged.

As the church responds to the changing patterns of sexual thinking and behavior, we need to move beyond the simplistic “Thou shall not” to the essential meaning of sex. That meaning can in part be garnered through human reason and experience. Millions of humans throughout history have understood something of the meaning of this act, the significance of procreation, the importance of fidelity, and the realities of what infidelity does to a marriage and family. But it is in the biblical story that we find a larger narrative that helps us understand and embody most fully God’s design for our sexuality. In particular, we understand sex in light of the biblical story and Christian worldview of creation, fall, redemption, and consummation. Beyond that framework our ethic must flow from the intended purposes or ends of sexual intimacy. I have set forth this approach in The Meaning of Sex: Christian Ethics and the Moral Life (Baker, 2009).

Good, but Finite and Fallen

Perhaps the most important thing Christians should say about sex is that it is a good gift of God from creation. In Gen 1, God pronounces as good a very physical/material world. The creation story is then climaxed with a very special creative act that includes sexuality and sex:

So God created human beings in his own image, in the image of God he created them; male and female he created them. God blessed them and said to them, “Be fruitful and increase in number; fill the earth and subdue it.” (Gen 1:27-28)

Immediately following, “God saw all that he had made, and it was very good” (1:31).

In Gen 2, Adam and Eve are brought together as male and female into a unique relationship of marriage: “For this reason a man shall leave his father and mother and be united to his wife, and they will become one flesh. The man and his wife were both naked, and they felt no shame” (2:24-25). Jesus himself affirmed this good creation and the sexual/marital paradigm (Matt 19:4-6), and Paul challenged false teachers who sought to undermine it (1 Tim 4:2-4).

Unfortunately, the church has often struggled with this theological affirmation of the goodness of sex. Asceticism with its denigration of the human body and things physical made a powerful but unfortunate impact upon the early church’s understanding of sex. Some Church Fathers taught that sexual intercourse resulted from the fall, others believed that marriage with its sexual intimacy was second-rate compared to a life of celibacy, and some early Christians even questioned the full humanity of Christ in the incarnation because of its bodily implications. Such asceticism is evident in Jerome in the 4th and 5th-centuries whose translation of the Bible into Latin became the “authorized version” for over a millennium. He once wrote “He who…in the married state renders his wife her due cannot so pray. Either we pray always and are virgins or we cease to pray that we may fulfill the claims of marriage” (A Select Library of Nicene and Post-Nicene Fathers [vol. 6; Eerdmans, 1979] 20). Through the Protestant Reformation and really up to the 17th-century Puritans, the church struggled with the notion of sexual goodness, seeing procreation as its primary and often only legitimate good.

If the church for 1500 years struggled to affirm the goodness of sex, today we struggle to affirm two other realities about sex—its finitude and its fallenness. All of God’s good creation is finite, and as such has very specific purposes and ends. Created realities like sex are not ultimate and are not intended to be the primary source of joy, meaning, and identity. Today sexual relations are given far greater significance than is warranted by their finitude. In so doing we have turned sex into an idol, thereby distorting its full meaning and beauty.

Because pleasure has become so vaunted today, some researchers find that humans are loosing the capacity for pleasure in sex. Psychologist A. Hart writes: “Today we have taken the pursuit of pleasure too far, and in so doing we have lost the ability to experience the very pleasure we are pursuing…. Consistent overuse of the brain’s pleasure circuits causes us to lose our capacity to experience pleasure” (Thrilled to Death: How the Endless Pursuit of Pleasure Is Leaving Us Numb [Nelson, 2007] xi). All of this stems from a failure to grasp the finitude of this good gift of God, and hence its role in human life is given undue proportion.

But of course Christian anthropology posits another reality about the human condition: we are also fallen creatures. All of God’s good gifts were distorted in the Fall. Human sexuality is still a good gift of God, but it is now marred in its longings, expressions, and goals. The story of the Fall in Gen 3 portrays four distortions that affect every area of life including the sexual realm. There is first a distortion in relationship with God so that we now seek our own meanings and patterns outside of God’s designs. Second, there are distortions within the human person bringing self-deception, guilt, hardened hearts, and disproportionate sexual desires called lust. Third, there are distortions in relationships so that sex can become a vehicle to control, manipulate, and harm the other. And finally, there are distortions in nature in that the whole of the natural world, including human genes, chromosomes, cells, and hormones are impacted, leading sometimes to sexual anomalies and distortions within the body and mind of a person.

The falleness of our sexuality and sexual drives mean that we cannot depend on what we feel within to determine our moral norms. Coupled with the falleness of society and culture that further distort our perceptions and actions, it is clear that we must return to God’s created designs to determine the norms for our sexual lives. When we look to God’s created designs we find that there are very specific purposes for this good, albeit finite and fallen gift. It is in these purposes that we find the norms, directions, and limits of sexual expression.

The Purposes of Sex

From both special revelation and natural revelation (i.e., reason, experience), we can discern four major ends or purposes of sex. God’s intention is that sex be experienced within the context of these four purposes. As will become clear, these purposes point to only one proper context—the marriage of a man and a woman. In providing insight into the meaning of sex, these purposes implicitly provide the moral norms.

The Consummation of Marriage: The closest we have to an explicit definition of marriage in the Bible is Gen 2:24: “For this reason a man will leave his father and mother and be united to his wife, and they will become one flesh.” This is a paradigmatic framework for marriage as evidenced by its use in other parts of the Bible, from Malachi to Jesus to Paul. It embodies three major components of marriage: a change of status recognized by the community (i.e., leaving father and mother), a covenant commitment (i.e., being united to each other), and a consummation through the sexual union (i.e., becoming one flesh).

Becoming one flesh is an explicit reference to sexual intercourse and consummates or completes the other elements of a marriage. The union of two bodies and souls sets this relationship apart from all other relationships. By nature, people sense that sexual intimacy is so profound that the relationship is never again the same. The apostle Paul argues against sexual immorality by noting that it embodies a life-uniting act without a life-uniting intent: “Do you not know that he who unites himself with a prostitute is one with her in body? For it is said, ‘The two will become one flesh’” (1 Cor 6:16).

The sexual union thus creates a new reality whereby the two become one, and this consummates their commitment and their change of status in the community (which is usually accompanied by legal procedures, religious ritual, and public celebration). It is the ultimate act of trust and self-giving to the other. As ethicist L. Smedes once put it, “The physical side of sexual intercourse is a sign of what ought to happen on the inside. It is the final physical intimacy. Two bodies are never closer: penetration has the mystique of union, and the orgasmic finale is the exploding climax of one person’s abandonment to another” (Sex for Christians [Eerdmans, 1994] 112).

Procreation: It is clear from both nature and Scripture (Gen 1:28) that sex is the means by which every new human life begins and by which life on earth continues. So that children are the fruit of marital love, God designed that a person comes into the world through this profound, one-flesh intimacy. Of course today many will contend that we need not think of sex as procreative, for we have the technical means to both control procreation and prevent it. The separation of sex from procreation is one of the most profound changes in the past century. Modernity, fixated on human control over the physical and biological world, has rendered sexual intimacy a non-procreative reality. Moreover, the new reproductive technologies have the capacity to separate reproduction from sex so that we cannot only have sex without children, but also children without sex.

From Genesis it is clear that sex and procreation belong together. We may debate whether every couple must intend to have children, but we must recognize that every sexual act is by nature a procreative act. Although I believe that we can make a case for stewarding our role in this area, and thus, utilizing ethical means of contraception, we ought not think of sex apart from procreation. Every sexual act carries with it during our fertile years the potential of bringing new life into the world. And even after fertility, it is still by nature a generative act that in principle points beyond the couple’s intimacy to the social dimension of sexual union.

Love: It is obvious by nature that when a man and woman love each other deeply they long to express it physically. Sexual intercourse is the most physical and intimate means of saying, “I love you.” It is of course not the only way a couple expresses their love, but it is a necessary means, which in turn further deepens their love.

Because the word eros is not used in the Bible to describe love, some have assumed that erotic or sexual love is secondary or even opposed to agape love. But the very fact that Scripture has one whole book devoted to the joys of love, including physical love, demonstrates its significance. The Song of Songs has sometimes been an embarrassment to the church and the Song has often been allegorized into a metaphor of God’s love for the church. But the Song’s vividness speaks for itself: “Like an apple tree among the trees of the forest is my beloved among the young men. I delight to sit in his shade, and his fruit is sweet to my taste. Let him lead me to the banquet hall, and let his banner over me be love” (2:3-4).

Nor is this reality lost in the NT. First Corinthians 13, the great love chapter is usually seen as the embodiment of Christian agape love. But this love is not far removed from the love of conjugal relations. “Love is patient…is not self-seeking” (vv. 4-5)—these words are directly applicable to sexual relations and demonstrate that agape love and eros love must go hand in hand in marital intimacy. Part of why God gave the gift of sex is for husband and wife to express and nurture their love.

Pleasure: Pleasure is not the invention of the devil. God is a God of pleasure not only in the eternal or spiritual sense, but within the created physical world. God created humans with bodily parts that have no other function than pleasure in the sexual act: the clitoris in the female and the glans penis in the male. An orgasm is evidence that we were wired for pleasure.

The pleasure dimension of sex is clear in Scripture. In the Song of Songs the bridegroom finds pleasure in the bride: “How delightful is your love, my sister, my bride! How much more pleasing is your love than wine…. Your lips drop sweetness as the honeycomb, my bride” (4:10-12). In encouraging sexual fidelity the Proverbs put it this way: “May your fountain be blessed, and may you rejoice in the wife of your youth. A loving doe, a graceful deer—may her breasts satisfy you always, may you ever be intoxicated with her love” (5:18-19). And the book of Revelation describes the final triumph as a delightful wedding, “I saw the Holy City, the new Jerusalem, coming down out of heaven from God, prepared as a bride beautifully dressed for her husband” (21:2).

It is important to note that, while God gave sex in part for pleasure, such pleasure is never isolated from the other purposes of sex. A morally legitimate sexual act brings together the consummation of marriage, procreation, love, and pleasure. And such is found only in the marriage of a man and a woman.

Conclusion

Sexual enticements are nothing new, but their pressures are experienced in new and more powerful ways than ever before. Thus, the church must respond by getting to the heart of the meaning of sex. It is a good and splendid gift of our Maker, but it is also finite and fallen. In contrast to the currents of our world, sex is not ultimate, unbounded, and free to follow its own whims and natural fallen desires. As a gift of God it finds its purpose as a created good in divine designs and purposes. It is only in the context of these purposes that we experience all that God intended when he made us sexual beings.