Why Do Christians Avoid Sex Outside of Marriage?

In a world where sexual freedom is often celebrated as a path to self-discovery and fulfillment, the Christian view of sex can seem old-fashioned or even restrictive. Why would anyone willingly say “no” to something so natural, pleasurable, and culturally accepted, especially when love and some level of commitment might already be present? For many who have never read the Bible or do not understand the Christian faith, it’s a mystery why Christians insist that sex belongs only within the bounds of marriage.

But for Christians, the choice to protect sex within the bounds of marriage isn’t rooted in shame or fear—it’s grounded in a deeper understanding of what sex is and its purpose. The Christian faith teaches that sex is not just a physical act or an expression of affection. Sex is a sacred gift from God, meant to reflect something far more profound: a covenant. At its best, sex is not just about pleasure or even procreation—it’s about two people becoming one in every sense, united in a bond of trust, love, and lifelong commitment under God.

This view isn’t arbitrary. It flows from Scripture, where we see marriage consistently portrayed as the exclusive, God-ordained context for sexual intimacy. From Genesis to Revelation, the Bible paints a picture of sex as a beautiful and powerful force—one that builds unity, expresses vulnerability, and mirrors the love between Christ and His Church. It’s precisely because sex is so meaningful that it is meant to be protected and revered, not cheapened or misused.

Let’s explore three primary reasons or rationales that Christians have for restricting sex to the confines of a covenant marriage relationship.

1. Scripture Affirms Sex Is Reserved for Marriage

At a base level, one of the foundational reasons Christians keep sex within marriage and find sex outside of marriage unacceptable is because God makes clear in the Bible that sex is meant to be confined to the bounds of a marital relationship. And for the Christian, obedience is important.

To be clear, the Bible rarely puts it so bluntly to say, “Sex can only happen within marriage.” However plenty of biblical passages speak to sexual immorality and promiscuity outside of a singular union between a man and a woman who are bound by a covenant.

Here are five passages that speak to the necessity of sex being protected within the confines of a covenantal, marriage relationship:

“Let marriage be held in honor among all, and let the marriage bed be undefiled, for God will judge the sexually immoral and adulterous.” – Hebrews 13:4

“Flee from sexual immorality. Every other sin a person commits is outside the body, but the sexually immoral person sins against his own body. Or do you not know that your body is a temple of the Holy Spirit within you, whom you have from God? You are not your own, for you were bought with a price. So glorify God in your body.” – 1 Corinthians 6:18–20

“For this is the will of God, your sanctification: that you abstain from sexual immorality; that each one of you know how to control his own body in holiness and honor, not in the passion of lust like the Gentiles who do not know God; that no one transgress and wrong his brother in this matter, because the Lord is an avenger in all these things, as we told you beforehand and solemnly warned you. For God has not called us for impurity, but in holiness.” – 1 Thessalonians 4:3–7

“Therefore a man shall leave his father and his mother and hold fast to his wife, and they shall become one flesh. And the man and his wife were both naked and were not ashamed.” – Genesis 2:24–25

“Now concerning the matters about which you wrote: “It is good for a man not to have sexual relations with a woman.” But because of the temptation to sexual immorality, each man should have his own wife and each woman her own husband. The husband should give to his wife her conjugal rights, and likewise the wife to her husband. For the wife does not have authority over her own body, but the husband does. Likewise the husband does not have authority over his own body, but the wife does. Do not deprive one another, except perhaps by agreement for a limited time, that you may devote yourselves to prayer; but then come together again, so that Satan may not tempt you because of your lack of self-control.” – 1 Corinthians 7:1–5

These Scriptures do not serve only as a means of helping us understand that sex is meant for the context of marriage alone, but they also serve as a means of helping us see that sex is the overflow of a covenant relationship.

2. Sex Is an Overflow of a Covenant Relationship

One of the most common misconceptions of sex in modern Western culture is that it is merely a physical act of pleasure. When the powerful act of sexual intercourse is reduced to a mere physical act of pleasure, it is easily mishandled to the point of destruction. Many Christians compare sex to fire. Like fire, sex is life-giving and beautiful when it is contained how it should be (like in a fireplace), and it is life-taking and destructive when it is not contained how it should be (like as in a wildfire or a house fire).

Christians have a higher view of sex than that it is merely a physical act of affection between two people. Christians believe that sex is meant to express a much deeper, spirit-level connection between a man and a woman who have committed to love each other unconditionally for life. Sex is not meant to be simply an act of affection, but more significantly, a reaffirmation of covenant promises between two people. In this way, sex is meant to be an overflow of a covenant relationship. Sex is pleasurable, but its purpose goes well beyond its pleasure.

When we reduce sex to nothing more than a pleasurable act of present affection rather than uphold its place as a selfless act of lifelong commitment, we cheapen sex and jeopardize the well-being of those involved.

And that leads to a third reason Christians avoid sex outside of marriage.

3. Marriage Protects the Vulnerabilities of Sex

Because sex is a deeply spiritual act between two individuals, those who have sex develop a deeper connection between one another than those who simply hug one another, hold hands, or engage in other, more platonic expressions of love. The deep, spirit-level connection formed by a sexually intimate relationship makes each party in that relationship feel some heightened level of vulnerability. This is natural. Whenever and however people open themselves up to others in an intimate way—emotionally, physically, or otherwise—it is natural to feel more vulnerable.

God knows everything about how humans work. He knows that sexual relationships create significant and real feelings of vulnerability. He knows that one of the most traumatic experiences a human can endure is being sexually abused or being taken advantage of in some other related way. Because God knows this about the power of sex and the makeup of the human mind and body, he knows that putting sexual activity behind the gate, if you will, of a marriage covenant helps protect the abuses and unnecessary vulnerabilities so often present in promiscuity.

Of course, this isn’t to say abuses of sex are not sometimes present in marriage. Unfortunately, sexual and emotional abuse can take place within marriage, too. But it is less likely to occur within the confines of a marriage covenant than it is outside of marriage. And, if such abuse occurs within a marriage, there is actual accountability (even alongside legal action), whereas if such abuse takes place in a random one-night stand, there is no such accountability (to a covenant or faith community), and the law is the victim’s only hope.

In God’s good design for sex, and for the good of those who engage in sexual activity, he puts it within the confines of a marriage covenant—a selfless, lifelong promise between a man and a woman—as a means of protecting people from the lack of accountability that comes with extramarital sex.

Sex Is a Gift

The list of reasons above that Christians reserve sex for the confines of marriage is far from exhaustive, but if you’re wondering why Christians think so differently than popular culture about sex and marriage, those reasons may help paint a bit of a picture.

God makes clear in the Bible that sex is reserved for a man and a woman who are united by the covenant of marriage. Christians who value obedience to the Word of God reserve sex for the confines of marriage for a whole host of reasons, and God has designed to be enjoyed in a way that is best for how he designed humans. We would be wise to consider how the Creator has made us to be in many ways, and especially regarding the deepest level of connections two humans can forge.

Sex is a gift from God, and Christians want to treat it for the gift that it is.