It is not a far stretch to say that most professing Christians in America do not possess a truly biblical sexual ethic. Even the term “biblical sexual ethic” is a turn-off for many, since it suggests that the Bible has an authoritative word to say about what we do with our bodies and how we respond to our sexual desires. Nevertheless, Scripture does set forth a clear sexual ethic. God has purposes for creating us as sexual beings, and those purposes help us to understand the boundaries that he has placed upon our sexual behavior.

While many may balk at the idea of boundaries for sexual behavior, virtually everyone has some lines they believe should not be crossed when it comes to sexual activity. Thankfully, with few exceptions, the conviction that pedophilia is wrong is still universal in America. This limitation fits within what appears to be the only true sexual boundary accepted by our current culture in Western countries: consent. However broad one’s sexual mores may be, consent sets a limit to what you may do and with whom you may do it. This is an ever-moving, fluid boundary, but a boundary nonetheless. The reason consent is accepted by so many today is that it preserves human autonomy, while protecting us, to some degree, from the sinful behavior of others. With consent as the sole limit, we retain to ourselves the right to be the rule-makers.

For Christians, though, God is the sovereign, rule-making measure of all things. He decides what is good and evil, and the fight to take that authority for ourselves drove human rebellion in the Garden and has driven it ever since. Sexual sin is a continuing part of our refusal to give God the glory he deserves and our desire to take his place as the rule-maker. But if God is real, then he sets the boundaries. The question then becomes, what boundaries has he established?


Put simply, the marriage of one man and one woman is the only place within which sexual activity is sanctioned and blessed by God. Any sexual activity outside the bounds of marriage falls into the category of sexual immorality, including homosexual behavior, heterosexual intimacy outside of marriage, and polyamorous relationships.

God created Adam first and then Eve in order to teach man about his need for a “suitable companion” or a compatible partner. Next, he joined man and woman together in a covenant that we call marriage. Moses writes, “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). Part of the joining of the two of them together involves their sexual union. That’s why we read about the two of them being “naked” and without shame. Adam’s and Eve’s sexual relationship within the very first marriage is not shameful. It is a glorious and good part of God’s design for human beings!

Not only is sex within marriage good and glorious, but the union of man and woman points beyond itself to the relationship that the Son of God shares with God’s people. Marriage (and sex) present a picture of the intimacy and commitment that exists between Christ and his bride, the church. Commenting on Genesis 2:24 (quoted above), Paul writes, “This mystery is profound, and I am saying that it refers to Christ and the church.,” (Ephesians 5:32). In other words, even in the beginning marriage was about Jesus. Sex is for the glory of God!


A polyamorous relationship is a sexual relationship involving more than one person. Thus, polygamy (one man and multiple women) and polyandry (one woman and multiple men) is ruled out of bounds. We may surmise that this the case since God created only one pair of human beings in Genesis 1-2 and united them in marriage. That union is the pattern for all future unions. The writer of Genesis comments, “Therefore a man shall leave his father and his mother and hold fast to his wife, and they shall become one flesh,” (Genesis 2:24).” In the New Testament, Jesus confirms that this is the pattern set forth by God, “Have you not read that he who created them from the beginning made them male and female, and said, ‘Therefore a man shall leave his father and his mother and hold fast to his wife, and the two shall become one flesh’?” (Matthew 19:4–5).

A man and a woman united in marriage. This is the biblical pattern. What then, shall we say about Abraham, Jacob, David, Solomon, and so many other heroes of the Old Testament who had multiple wives? Does the Bible’s depiction of these men of faith sanction polygamy? In short, no. We need look no further than Jesus’ teaching in Matthew 19 where he confirms Genesis 2 (one man and one woman) as the pattern for marriage and sex to see that God permitted such things in the past without condoning them. There, Jesus comments on the laws governing divorce found in Deuteronomy. After concluding that divorce is not permissible in the light of God’s will expressed in Genesis 2:24, his conversation with the Pharisees continues:

They said to him, “Why then did Moses command one to give a certificate of divorce and to send her away?” [see Deuteronomy 24:1-4] He said to them, “Because of your hardness of heart Moses allowed you to divorce your wives, but from the beginning it was not so. And I say to you: whoever divorces his wife, except for sexual immorality, and marries another, commits adultery.” (Matthew 19:7–9)

Here’s the lesson: God can regulate or place limits upon sinful behavior without sanctioning that behavior. The Law of Moses often does this. God does not give his approval to all that he temporarily permits before the coming of Christ and the ushering in of the New Covenant. These laws are designed for a Spiritless, often faithless people who are part of a theocratic nation. Polygamy is another example of behavior that God permits and even regulates without approving of it during the time before the New Covenant, when God’s Spirit would fill all those who trust in his Son and become part of a greater, spiritual kingdom.

We can see God’s disapproval of polygamy communicated in the inspired record of history as each polygamous relationship recorded in the Old Testament results in disastrous and damaging consequences. Abraham’s relationship with Hagar produced a centuries-long conflict between the descendants of Ishmael (Hagar’s son) and Isaac (Sarah’s son). The jealousy that began with these two mothers endured far beyond their lifetimes. Jacob’s wives fought for his affection and passed that battle on to their children. David’s children by different wives brought about incest and rape and murder. Solomon’s many wives drew his heart away from pure devotion to him and brought idolatry back into the land. While God is still at work in and through the sinful actions of these men, their departure from the biblical pattern for sexuality and marriage is never approved of by God or the writers of Scripture.


While there are some defenders of polyamory today, the outcry against the Bible’s teachings on homosexuality (whether gay, lesbian, queer or transsexual relationships are in view) is much more pronounced. If you voice any opposition to same-sex relationships, then you are unloving. You are a bigot. You are to be excluded and silenced. Yet for nearly two-thousand years the Christian church has unanimously condemned all homosexual behavior. Pleas for the acceptance of homosexuality (and other forms of sexual immorality) within the church have only been raised in the last few decades. These pleas are not only out of sync with Christian history, but more importantly with Scripture itself.

In Romans, Paul, once again alluding to God’s original design in creation, describes homosexual behavior as “unnatural.” In his discussion of the sinfulness of humankind, he moves from portrayals of the sin of idolatry to descriptions of sexual sin.

 Therefore God gave them up in the lusts of their hearts to impurity, to the dishonoring of their bodies among themselves… God gave them up to dishonorable passions. For their women exchanged natural relations for those that are contrary to nature; and the men likewise gave up natural relations with women and were consumed with passion for one another, men committing shameless acts with men and receiving in themselves the due penalty for their error. (Romans 1:24–27)

The word “shameless acts” comes from the same root word we see represented in the version of Genesis 2:25 (“they were naked and unashamed“) with which Paul’s readers would have been most familiar. God clearly intended for men to be joined in sexual union with women and vice-versa. To go against this design is “unnatural.” It is deemed “shameful.” In short, it is sinful.

Like all sin, homosexual behavior brings God’s judgment:

Or do you not know that the unrighteous will not inherit the kingdom of God? Do not be deceived: neither the sexually immoral, nor idolaters, nor adulterers, nor men who practice homosexuality, nor thieves, nor the greedy, nor drunkards, nor revilers, nor swindlers will inherit the kingdom of God. And such were some of you. But you were washed, you were sanctified, you were justified in the name of the Lord Jesus Christ and by the Spirit of our God. (1 Corinthians 6:9–11)

The words translated “men who practice homosexuality” refer to both partners in a male homosexual act. Men who participate in homosexual relationships, like all sinners (idolaters, adulterers, thieves, etc.) will not enter into God’s Kingdom.

Scripture’s condemnation of homosexuality is part of a much larger condemnation of sin in general (see Romans 1). All of us are born sinful. We inherit a sinful nature from our first fallen father, Adam (see Romans 5:12-21). As Paul says, apart from Christ we are all “dead in sin” and “by nature children of wrath,”(Ephesians 2:1-4). We cannot defend any sinful desire or inclination by pointing to innate desires or lifelong attractions. There is no reason for a Christian to deny that someone may be “born this way,” with respect to homosexual desires. All of us are “born this way,” when we consider the different expressions that our sinful natures have within us. Our hearts are corrupt (Genesis 6:5; Jeremiah 17:9). This corruption may show itself in a propensity toward anger, jealousy, or sinful sexual desires. Just as we would not excuse these other sinful inclinations, so we should not treat same-sex attraction as morally neutral. Paul not only speaks of putting to death sinful behaviors, but also evil desires: “Put to death therefore what is earthly in you: sexual immorality, impurity, passion, evil desire, and covetousness, which is idolatry,” (Colossians 3:5, emphasis added)

We may struggle to communicate this truth in today’s world, but our wrestling with and the world’s rejection of God’s truth does not diminish Scripture’s authority. We must speak the truth with love for others and a concern for more than their temporary satisfaction. We must be willing to gently, lovingly share the Gospel with people of all backgrounds and persuasions. This means that we will have to talk about the reality of sin and the necessity repentance. If we neglect these realities, we lose the Gospel. If we lose the Gospel, we will be left with no hope to offer to a hurting world.


Of course, we need to recognize that Scripture devotes far more space to condemnations of heterosexual sin than it does to homosexual sin. While the Bible’s teaching on homosexuality is clear, too great a focus upon this particular sin will blind the rest of us to our own sin and make us hypocrites. All sexual activity outside of marriage (understood as the union of one man and one woman) is sinful. The Bible condemns adulterous relationships and all forms of sexual immorality in the passage quoted above from 1 Corinthians: “Or do you not know that the unrighteous will not inherit the kingdom of God? Do not be deceived: neither the sexually immoral, nor idolaters, nor adulterers…” (1 Corinthians 6:9, emphasis added). “Sexually immoral” refers to any and all sexual acts outside of marriage. Adultery refers to sex between a married person and someone other than his or her spouse. Biblically, sex before marriage is sinful. Sex with someone not your spouse is sinful. Incestual acts are sinful (Deuteronomy 27:22; Leviticus 18:9-11; 20:17-19). Bestiality is sinful (Leviticus 18:23; 20:15-16). Even lustful thoughts directed at anyone other than one’s spouse are sinful (Matthew 5:27-28). The Bible does not have an unbalanced focus on any one form of sexual immorality. Sex is for marriage. All deviations from this God-given norm are a transgression of God’s Law and sin in his eyes.


This means, of course, that all of us are guilty of sinful sexual behavior and thoughts. We cannot point to others and claim to be free of the stain of sexual sin. The Good News is that no matter the form or frequency of our failures in the arena of sex, we can be forgiven and cleansed. We can be put in a right relationship with God the Father through faith in the sin-bearing work of the Son.

Therefore, if anyone is in Christ, he is a new creation. The old has passed away; behold, the new has come. All this is from God, who through Christ reconciled us to himself and gave us the ministry of reconciliation; that is, in Christ God was reconciling the world to himself, not counting their trespasses against them, and entrusting to us the message of reconciliation. Therefore, we are ambassadors for Christ, God making his appeal through us. We implore you on behalf of Christ, be reconciled to God. For our sake he made him to be sin who knew no sin, so that in him we might become the righteousness of God. (2 Corinthians 5:17–21)

Let us rejoice in Paul’s declaration after his description of those who will not inherit the Kingdom of God: “And such were some of you. But you were washed, you were sanctified, you were justified in the name of the Lord Jesus Christ and by the Spirit of our God,” (1 Corinthians 6:11).

Sometimes God’s work of forgiveness is followed with full and immediate release from temptation to particular sexual sin. A man fully embroiled in pornography may experience a full release from that temptation when he puts his faith in Christ. On the other hand, he may continue to struggle with that temptation. A woman who has been attracted to other women her entire life is forgiven of all her sin the moment she trusts in Christ and repents. She may at that moment find those old desires gone or greatly weakened. She may even find them to be replaced by new desires. One the other hand, she may find little changed in her sexual desires. She may struggle with same-sex attraction for many years to come or for the rest of her life. The key word here is “struggle.” Our new identity in Christ means that we have to fight off the attempts of our sinful nature to reassert itself.

If then you have been raised with Christ, seek the things that are above, where Christ is, seated at the right hand of God. Set your minds on things that are above, not on things that are on earth. For you have died, and your life is hidden with Christ in God. When Christ who is your life appears, then you also will appear with him in glory. Put to death therefore what is earthly in you: sexual immorality, impurity, passion, evil desire, and covetousness, which is idolatry. On account of these the wrath of God is coming. In these you too once walked, when you were living in them. But now you must put them all away: anger, wrath, malice, slander, and obscene talk from your mouth. Do not lie to one another, seeing that you have put off the old self with its practices and have put on the new self, which is being renewed in knowledge after the image of its creator.  (Colossians 3:1–10)

If we have been raised with Christ then we have also died with Christ. We have died to who we once were. Therefore, we must put to death things such as sexual immorality, impurity, evil desire and anger, wrath, malice, and obscene talk. Forgiveness and a new status before God comes to us the moment we trust in Christ. The rest of our lives in this world are to be lived in the pursuit of holiness.

Have you been washed? Have you been made new? Have you put your trust in the sin-bearing work of Christ? Have you exchanged your unrighteousness for his perfect righteousness? The promise still stands, “If you confess with your mouth that Jesus is Lord and believe in your heart that God raised him from the dead, you will be saved,” (Romans 10:9). Saved from sin. Saved from sexual sin. Saved by Christ and for Christ.

Are you presently engaged in the fight against all sin, including the temptation to sexual sin? Are you committed to “put to death the deeds of the body,” with the Spirit’s help and power (Romans 8:13)? Holiness and ever-increasing, everlasting happiness are found, not in giving in to that which the God condemns, but in pursuing conformity to the One who made us and redeemed us for himself.