Imagine paying an exorbitant price for something precious. Once you became the owner you’d protect that possession. You would preserve it for its intended use.

God paid an outrageous price for you, the blood of Jesus Christ, His Son. He has redeemed us, bought us. From this position of great cost and love He reveals His will for our lives: sanctification. We are to become set apart, clean, set aside for His intended use.

Paul builds on this: “This is the will of God, your sanctification: that you abstain from sexual immorality” (1 Thessalonians 4:3). A major area of sanctification is our sex life. To be sanctified, clean, set apart, we must abstain from sexual immorality. Christians know this. Deep in our conscience, we know this. But the Spirit — here in 1 Thessalonians 4:4-8 — reminds us.

In this little section Paul teaches us the ‘how’ and ‘why’ of abstinence from sexual immorality.

The What.

First, however, we must deal with the subject of sexual immorality itself. The Thessalonian church swam in a culture that had given themselves over to it. Many of us live in the same experience. Fornication (sexual activity outside marriage), adultery, homosexuality, pedophilia, and pornographic erotica existed in their culture, as it does ours. All this fits under the banner of sexual immorality.

It is easier to define sexual morality: sexual activity between a heterosexual married couple. This is the biblical norm. Activity outside that is sexual immorality. Again, God’s will for Christians is that we’d be set apart from that.

Our society might believe human bodies have a simple biological urge for sex that must be exercised. For them, as long as an activity is consensual, it is fine. For them, casual sex is actually a thing. For them, sexual compatibility must be tested. For them, sexual fulfillment is of extremely high importance. For them, cohabitation is required before marriage. For them, all this is right and good. For them, this is moral.

But not for us. The believer in Christ is called to a different, sanctified, life. We aren’t disciples of our society, but of Jesus Christ. Clearly, this puts some of us in a position where we swim against the current.

Early Christians who came out of Judaism didn’t have this particular battle to fight. Judaism embraced the Biblical sex ethic already. No, they had other battles. But Christians who came to Christ out of Gentile paganism were called to live a very different sex ethic than their neighbors.

But how? Why? To this, Paul continues the thought to the Thessalonians. Let's observe.

The How.

Control Your Own Body

“…that each one of you know how to control his own body in holiness and honor…” (1 Thessalonians 4:4)

The first ‘how’ is actually more of an explanation on the ‘what.’ We are to abstain from sexual immorality; this means we will 'control' our own bodies. Every believer is called to 'control' their own body. This is the aim.

This helps us understand how this work is done. Notice how Paul thinks. To him, the body follows the person. Each one, he writes, "controls his own body." In other words, my body is mine, but I am not my body. I am in my body, but my body is not fully me, not entirely me.

The Corinthian church battled sexual immorality. Some in that church borrowed an argument from culture. They said, the stomach is only satisfied with food (my paraphrase). Their argument then: our bodies will only be satisfied with sex. Paul explained to them: “the body is not meant for sexual immorality, but for the Lord, and the Lord for the body” (1 Corinthians 6:13).

In other words, don’t buy into the logic that your body is only satisfied with sex. This doesn’t actually happen: the satisfaction isn't real as it leads to greater desire. Most bodies are capable of sexual activity, but that is not the end purpose of the body. Paul’s point: Your body is meant for God. It is capable of sex, but it is meant for God.

Expect To Live Counter-Culturally

“…not in the passion of lust like the Gentiles who do not know God…” (1 Thessalonians 4:5)

The Gentile world did not know God. They hadn’t received Christ, so they were not reconciled to God. If they had, they could have received the biblical sex ethic. But they hand’t. They could not be expected to live as if they had.

The believer is different. The believer must expect to live counter-culturally if he is going to experience sanctification in this area. The Thessalonian church had to realize how different they would be.

As a believer, you must expect your lifestyle will be different. Your society might embrace a different sex ethic as normative, but God has a different brand of life for you. “Flee sexual immorality” (1 Corinthians 6:18).

Consider Others Over Yourself

“that no one transgress and wrong his brother in this matter…” (1 Thessalonians 4:6)

The truth is when a believer engages in sexual immorality it impacts everyone. It does not only influence them, but others. When we enter into sexual sin we hurt more than ourselves.

First, we hurt the person we have entered into the sin with. They have become cheapened, operating in less than the image God gave them. They have given a piece of themselves away. Even if they are a person on a digital screen, they have been hurt in that exchange.

Second, we hurt those close to us. Our families (or future families) are harmed by our sexual sin. Husbands are weakened, disabled from leadership and love in their marriage. Fathers become less than what they could have been. Families are broken up. Friendships are strained. Community groups become awkward. Your sexual sin hurts these relationships.

Third, we hurt the body of Christ. You might not ever meet the believers from China. Yet, in an unseen but very real way, your sexual sin hurts them. The reason for this is simple: sexual sin weakens the church, locally and universally. When the church is weakened in one place, all the body suffers with it. You might feel it's a drop in the bucket, but it isn’t.

This is part of the reason Paul urged the Thessalonians to make certain they didn’t wrong their brother in this matter. Consider the seriousness of stumbling a brother with the words of Christ: “but whoever causes one of these little ones who believe in me to sin, it would be better for him to have a great millstone fastened around his neck and to be drowned in the depth of the sea” (Matthew 18:6).

The Why.

“…because…” (1 Thessalonians 4:6)

There is, of course, the question of why. Some of this is already seen in the how, but Paul takes the time to say, “because.” He is willing to give us a few reasons to pursue sexual purity and morality in our lives.

Understand, this is grace. God is under no obligation to tell us why he wants us to behave in certain ways. He is God, He is Lord. We are to submit to Him. Still, His commands are for good reason. His love means His commands are for our best. To live a life of sexual morality is the best version of life. God designed it to be this way.

Here are some of the reasons Paul gives:

God’s Vengeance

“…the Lord is an avenger in all these things, as we told you beforehand and solemnly warned you…” (1 Thessalonians 4:6)

God is the avenger in this area of life, and in all areas. There is the final judgement, of course, but God is busy working even now. Obedience leads to great blessing, while sin has pain embedded within it.

Don’t expect to get away with sexual sin. It is crippling. As I wrote above, sexual sin leads to damaged people, damaged marriages, and damaged families. Divorce, disease, and disappointment flow from sexual sin. The hand of the Lord is removed from your life. The blessing of God begins to dry up.

This is a major reason for sexual purity: “Because the Lord is an avenger in all these things.” We know God doesn’t let this activity slide. We know He is going to judge it eternally. We know Jesus shed His blood for this. How could we act as if it is acceptable to enter into? We can’t.

God’s Calling

“…For God has not called us for impurity, but in holiness…” (1 Thessalonians 4:7)

God has put a calling upon our lives. If you’re a believer, you are resting in His election. He chose you. You rejoice at His adoption, His grace.

To willingly persist in sexual sin disregards this calling. The urging of the New Testament is clear: “walk in a manner worthy of the calling to which you have been called” (Ephesians 4:1). We must say to ourselves, “In Christ, I am better than this. God has remade me. He has a purpose for me. This isn’t it.”

God’s Spirit

“…Therefore whoever disregards this, disregards not man but God, who gives his Holy Spirit to you…” (1 Thessalonians 4:8)

Finally, Paul gives the incredible reason that God’s Spirit has been given to believers. He lives within us. God’s Spirit urges us to obey, to live for God. He urges us to follow hard after God.

“And I will put my Spirit within you, and cause you to walk in my statutes and be careful to obey my rules” (Ezekiel 36:27). This is promised to us. The Spirit within us would not lead us into sexual sin. If we go there, it is not because God’s Spirit is leading us. No, something else has led us there.

“But I say, walk by the Spirit, and you will not gratify the desires of the flesh” (Galatians 5:16).

Close.

God has given us so much in Christ. I want to live a life of gratitude to God. My Father, by His word and His Spirit, has told me how to live. He has given me reasons to trust and obey Him. I will follow.

Imagine a slave who has been set free. Imagine that slave going back to his original slavery. The one who set him free would watch in bewilderment.

Let us not go back to slavery. Christ has set us free.