Introduction

(Read 1 Thess. 4:3-8)

For many people—especially those of the younger generations—it’s passages like this that are a real hurdle for them in accepting Christianity as true. The Bible is just so “out of touch” with the reality of the world that we live in today.

There are at least a couple of reasons for that. One reason is that we’re constantly being told about the “big” and even “apocalyptic” problems facing the world (e.g., mass shootings, the refuge crisis, racial tensions, climate change, etc). It leaves some young people wondering, Why would God even care about what people do in the privacy of their own bedrooms on the weekend? It seems like small stuff compared to the big problems.

Another reason is that people are very uncomfortable with someone or something “outside” of us telling us how to live out something as deeply personal as our gender and sexuality. The philosophy of our day says that your true sexual identity is discovered by “looking within” yourself. There’s concern about “being authentic” and living out the “true you” that is within. We are told to “live your truth,” “follow your heart,” “you do you,” “be true to yourself,” and “find yourself.”

So, when the Bible starts “meddling” by telling us how to express our gender and sexuality, it sounds strange and even oppressive! Especially in its very blunt command: “For this is God’s will, your sanctification: that you keep away from sexual immorality” (v. 3).

Sexual immorality—the Greek word πορνεία—is a broad word that covers all sorts of sexual expression outside of the marriage covenant between one man and one woman. It prohibits sex in all sorts of contexts: premarital, extramarital, same-sex, and so on.

And because God is not just concerned about outward sexual acts but also about the inward purity of the heart, πορνεία forbids the sin of lust and sexual fantasy as Jesus made clear in Matthew 5:27-30.

God is giving us a comprehensive command when he tells us to keep away from sexual immorality!

But why would God give us such a hard command? Why would he give us such a difficult prohibition that is so out of touch with our world? Is he trying to crush us? Oppress us? Damage us? Break us? NO! Jesus said that he came to give us an abundant life (John 10:10), so he’s actually wanting to bless us with his wisdom with sex!

The passage gives us two reasons why we should use God’s wisdom—not ours—with sex.

Sex Is Bigger Than We Often Realize (vv. 3-5)

In today’s world, sex is “just sex.” Sitcoms portray casual sex as the norm. Sex scenes within movies are pervasive which desensitize us. Many streaming services offer content with graphic sex scenes that can be invited into our homes with a click of a remote button. Sex is presented as a bodily appetite, a physical need. An itch to be scratched. Sex is … “just sex.”

We might be tempted to think that this is all new. Maybe some of it is but not the casual attitude toward sex. One of the ancient Greeks said, “Mistresses we keep for the sake of pleasure, concubines for the daily care of our persons, but wives to bear us legitimate children.” That was then just like now. Sex was seen as “just sex”!

Paul combats the attitude of “just sex” by elevating sex to a higher level. He doesn’t agree with the “just sex” attitude. That brings sex down to the level of one more appetite to satisfy. Instead, Paul wants to elevate sex to be used in “holiness and honor.” He wants us to think of sex in God’s original design—as the “covenant glue” between a husband and wife.

I’ve heard it said by Tim Keller that sexual immorality is to sex what inflation is to the economy. That’s a good way of putting it because we all feel the burden of inflation in recent days. The same number of dollars does not bring home the same amount of food from the grocery store. The same paycheck does not get us as much.

Sexual immorality is like inflation. It cheapens sex. It damages our ability to enjoy and experience sex to our fullest potential in the covenant of marriage. It destroys our ability to experience the abundance of life that Jesus has for us.

This reality of why God says, “No,” to sexual immorality makes it clear that God is not anti-sex. He’s not just into rules. He’s not trying to flex his muscles. God command to avoid sexual immorality is a guardrail to protect us from devaluing this great gift that he has given.

This passage gives us a second reason why we should use God’s wisdom—not ours—with sex.

Sex Is More Powerful Than We Often Admit (v. 6)

Among other things this is saying that sexual immorality hurts those around us. That’s not actually hard to believe, is it? Think of the pain caused by an unfaithful spouse. Infidelity wounds the other person, and it takes a lot of healing to recover from the wound. The children in a family where a parent has been sexually immoral always feel the negative impact on some level. Every kid wishes that his or her parents had remained faithful.

Sometimes that “brother or sister” who has been sinned against is yourself. Pornography—a HUGE problem in our day—does damage to our soul and our brain. We’ve only learned in recent decades just how our brain is rewired negatively by a steady use of pornography. The ability to see people as images of God is damaged and people are turned into objects for our visual gratification. We are damaged by pornography.

At other times that brother or sister who is sinned against is the body of Christ at large. When leaders—high profile and highly respected leaders—fall into immorality, it does damage to the witness of the body of Christ. Skeptics find justification for being skeptical.

Sex is never … “just sex.” The old analogy is that sex is like fire in the fireplace. In the fireplace, it is good. It keeps us warm. We can cook food on the fire. We can sit in the ambiance of the fire’s glow. But fire in the kitchen is damaging and deadly.

Sex is a gift from God that needs to be used with God’s wisdom—not our own—to use it for the good of ourselves and others.

But maybe you see the reason for God’s prohibitions for sex, but you still need a bit of a nudge. Verses 7-8 give us the nudge that we need. The passage ends with a severe warning!

Do Not Reject God’s Wisdom About Sex (vv. 7-8)

Why does God speak so forcefully about avoiding sexual immorality? Why does he lay it on so thick? Why does he warn us that to reject this teaching about sexual immorality is to reject his Holy Spirit?

I believe there are a couple of reasons why God warns us so forcefully.

First, he warns us so forcefully because the world—ancient and modern—teaches so pervasively that sex is “just sex.” Since sexual desire is such a powerful desire within us, we need an equally powerful warning about surrendering our use of it to God’s wisdom!

Secondly, we need a powerful warning to avoid sexual immorality because we are so tempted to compromise in our morally compromised world. That’s true even as Christians. It’s easy to tell ourselves that if we are 90% committed to God, that’s good enough. That if I keep for myself this “little area” of lust and sexual sin, God won’t really mind. That God is content with having most of me.

God isn’t content with “most of you.” God saved all of you and he purchases all of us by the blood of Jesus Christ. And God wants all of you!

We can easily lie to ourselves. Is it really that big of a deal if I click on that link and check out a few pictures? Is it really that big of a deal if I get a little flirtatious with that friend or coworker? Is it really that big of a deal if I have a one-night stand when I’m single? Is it really that big of a deal if I my eyes wander and linger on those around me? Is it really that big of a deal if I let my thoughts drift into immorality? Is it really that big of a deal if I am too physically permissive with my fiancé?

God’s answer is simple: “Yes.” God didn’t call us to impurity. God called us to holiness and honor. And anyone who rejects this instruction—to keep away from sexual immorality—rejects not a man’s word but God’s word.

Conclusion

Sex is bigger than we often realize and more powerful than we often admit. So, let God’s wisdom guide your sex life. Don’t try to be wiser than God. Don’t think that you’re emotionally or psychologically mature or healthy enough to know what’s good and what’s not good with your sex life. Let God’s wisdom guide your sex life. Because God wants you to be blessed!

If you’re dabbling around sexual immorality—in deed or in thought—can I call you to hear the word of the Lord? Can I call you from the dangerous place of rejecting God’s instruction with this? You can’t play with fire and remain unburned. You can’t use your own wisdom and think that you’ll experience the abundance that Jesus has for your life.

But if you are someone who has been involved in sexual immorality but have repented, I want you to know how much grace God has toward repentant sexual sinners! “If we confess our sins, he is faithful and righteous to forgive us our sins and to cleanse us from all unrighteousness” (1 John 1:9, CSB). But in this moment, repent! Turn around! Follow God! From this day forward, let God’s wisdom guide your sex life. And know that God’s mercies toward repentant sexual sinners are new every morning! Amen.

Matthew LaTourelle is a ThM in Ministry student at Gordon-Conwell Theological Seminary and the pastor of Marcell Community Church located in rural Northern, MN.