Short answer: The Bible forbids all sexual activity outside the marriage of one man and one woman. That includes sex before marriage (fornication), adultery, incest, same-sex sexual activity, prostitution, and lust of the heart, which takes in pornography. Within marriage, Scripture honors sexual intimacy as a gift, asks for faithfulness and mutual consideration, and does not give a list of permitted or banned acts.
In This Article
- What Are The Forbidden Sexual Activities In The Bible?
- What Counts As Sexual Sin Outside Of Marriage?
- What Does The Bible Say About Homosexuality?
- Are Lust, Pornography And Masturbation Sinful?
- What Is Sinful In The Marriage Bed?
- What Does God Say About A Sexless Marriage?
- Key Bible Verses About Sexual Sin
Questions about sex are some of the ones most often whispered rather than asked out loud, so it is no surprise that people type them into a search bar late at night. Behind many of them is a sincere wish to please God, and behind others is guilt, confusion or hurt. I want to answer plainly and without crudeness.
The Bible speaks with remarkable clarity on the boundaries of sexual behaviour, and with great warmth about sex as God's design. Both halves matter. If you are looking for the narrower word behind these verses, see What Does Porneia Mean In The Bible?
What Are The Forbidden Sexual Activities In The Bible?
Here is a quick reference of what Scripture addresses and where to read more. This is a summary, not a complete list; the New Testament word porneia works as an umbrella for them all.
| Activity | Key passages | Read more |
|---|---|---|
| Sex outside marriage (fornication) | 1 Corinthians 6:18-20; Hebrews 13:4 | Premarital sex |
| Adultery | Exodus 20:14; Matthew 5:27-28 | Adultery |
| Incest | Leviticus 18; 1 Corinthians 5:1 | Incest |
| Same-sex sexual activity | Leviticus 18:22; Romans 1:26-27 | Homosexuality |
| Lust and pornography | Matthew 5:28 | Watching porn |
| Rape and the abuse of children | Throughout, as violence and injustice | Rape, pedophilia |
The thread through all of these is the same. God made sex to be shared by a husband and wife in a covenant, and every departure from that pattern damages people, relationships, or both. For a wider survey of the passages, see Examples Of Sexual Sin In The Bible.
What Counts As Sexual Sin Outside Of Marriage?
Two sins stand out, and they are linked: fornication and adultery. Fornication is sexual activity between people who are not married to each other. The writer of Hebrews gives the rule in a single sentence:
Marriage should be honored by all, and the marriage bed kept pure, for God will judge the adulterer and all the sexually immoral.
Hebrews 13:4 (NIV)
Paul explains why it is not a small thing in 1 Corinthians 6:18-20: we are to honor God with our bodies because they belong to him. Adultery is the breaking of a covenant on top of that. It appears in the Ten Commandments (Exodus 20:14), and Proverbs 6:32-33 describes the wounds and dishonor that follow. It wrecks trust and, too often, the marriage. See The Ten Commandments for more on the seventh.
Jesus pressed this beyond actions. He did not accept that a person is faithful just because they have kept their hands to themselves.
What Does The Bible Say About Homosexuality?
The Bible treats same-sex sexual activity as sin. Leviticus 18:22 prohibits it under the law given to Israel, calling it a detestable practice in the NIV. In the New Testament, Paul addresses it in Romans 1:26-27 as a result of humanity's turning away from God's created order, and again in 1 Corinthians 6:9-11. This is the historic Christian reading of those passages and the one I hold.
I also want to be just as clear about the other side. The same Bible tells us that every one of us falls short, and that the answer to sin is Christ's forgiveness and transforming power, not contempt. People who experience same-sex attraction are to be met with empathy and respect, and invited to follow Jesus like everyone else. Where we speak the truth, we speak it in love. I have a longer discussion in What Does The Bible Say About Homosexuality?
Are Lust, Pornography And Masturbation Sinful?
The Bible does not mention pornography by name, because the technology did not exist, but the principles are not obscure. Jesus taught:
But I tell you that anyone who looks at a woman lustfully has already committed adultery with her in his heart.
Matthew 5:28 (NIV)
Pornography feeds precisely the desire Jesus is describing. It also turns real people into objects, trains the mind to seek gratification without commitment, and can place a deep strain on marriages. Our articles on watching porn and lust go deeper, including practical steps for those struggling.
Masturbation is not named in Scripture either. The question turns on what is happening in the mind, and since it is almost always tied to lustful thoughts, most pastors counsel against it. I explain the reasoning, and how to approach the struggle with grace, in Is Masturbation A Sin In The Bible? If you are caught in a habit that feels beyond your control, you are not alone, and addiction is something the church should help with and not hide.
What Is Sinful In The Marriage Bed?
Many sincere couples ask this, and they are looking for a list. The honest answer is that the Bible does not give one. It honors the marriage bed, calls it pure, and sets principles rather than rules about particular acts.
Those principles are worth holding on to:
- Faithfulness. Sexual intimacy is for the two of you alone, in thought as well as deed.
- Mutual love and consent. Nothing that is forced, pressured, degrading or that one spouse is uncomfortable with fits the way Christ calls us to love.
- Purity of mind. What you bring into the bedroom, including images from outside the marriage, should not come from lust or from pornography.
- Honest conscience before God. If you cannot do something in good conscience, do not do it. See Romans 14:23.
Specific questions about particular acts are covered in Is Oral Sex A Sin In The Bible? and Is Anal Sex A Sin In The Bible?. If you have a question you are embarrassed to ask, talk it over with a trusted pastor or a Christian counselor, and bring it to the Lord in prayer.
What Does God Say About A Sexless Marriage?
Scripture takes it more seriously than many couples do. Paul writes to the Corinthians:
Do not deprive each other except perhaps by mutual consent and for a time, so that you may devote yourselves to prayer.
1 Corinthians 7:5 (NIV)
He frames marital intimacy as something husband and wife owe each other in love, not as a tool or a weapon. Long-term refusal can leave a spouse lonely and tempted. At the same time, there are real reasons a couple may go through a dry season: illness, grief, pain, trauma, medication, exhaustion. These call for patience and compassion, not accusation. Talk honestly, see a doctor or counselor if needed, and seek help from your church. The aim is to serve each other.
Key Bible Verses About Sexual Sin
- Hebrews 13:4: honor marriage and keep the marriage bed pure.
- 1 Corinthians 6:18-20: flee sexual immorality and honor God with your body.
- Exodus 20:14: the commandment against adultery.
- Matthew 5:27-28: Jesus on lust and adultery of the heart.
- Leviticus 18:22 and Romans 1:26-27: same-sex activity named as sin.
- 1 Corinthians 7:3-5: husband and wife owe each other intimacy.
- 1 John 1:9: confess, and God forgives and cleanses.
Frequently Asked Questions
What are the forbidden sexual activities in the Bible?
Sex outside marriage, adultery, incest, same-sex sexual activity, prostitution, rape and lust of the heart, including pornography. The New Testament gathers most of these under the word porneia, sexual immorality. See Examples Of Sexual Sin In The Bible.
What counts as sexual activity in the Bible?
The Bible speaks of sexual union itself, but also of the desires and acts that lead toward it. Jesus said that looking lustfully is adultery of the heart, so sexual sin includes the thought life as well as outward behaviour.
What is sinful in the marriage bed?
The Bible honors the marriage bed and does not list approved or banned acts. It points to faithfulness, mutual love and consent, purity of mind and a clear conscience. Anything coercive, degrading, or fed by pornography or outside lust does not fit those principles.
Is it okay to masturbate in Christianity?
Scripture does not name it, but it is nearly always tied to lustful thinking, which Jesus addressed in Matthew 5:28. Most pastors counsel against it while urging grace for those who struggle. I discuss the reasoning in Is Masturbation A Sin In The Bible?
What does God say about living in a sexless marriage?
Paul tells married couples not to deprive each other except by mutual consent and for a time (1 Corinthians 7:5). Seasons of illness, grief or stress are real and call for compassion. A lasting pattern of refusal deserves honest conversation, counseling and help from your church.
Can God forgive sexual sin?
Yes. Paul told former adulterers and the sexually immoral in Corinth that they had been washed and justified in Jesus's name. Confess, repent and rely on others to help you walk in purity. See Does God Forgive All Sins?
