Seven Reasons to Pursue Sexual Purity

The main thought in 1 Thessalonians 4:1–8 is found in verse 3: “For this is the will of God, your sanctification: that you abstain from sexual immorality.” Blunt, clear, and straightforward as it is, God in his kindness and patience with us also surrounds this command with several reasons why we should obey it. These are clear from the text. I hope they will be helpful for each of us as we pursue obedience to Christ in this issue.

1. Living in sexual purity is “how you ought to walk and to please God.”

1 Thessalonians 4:1 – Finally, then, brothers, we ask and urge you in the Lord Jesus, that as you received from us how you ought to walk and to please God, just as you are doing, that you do so more and more.

We’re told elsewhere in Scripture that we should “walk in a manner worthy of the Lord, fully pleasing to him” (Colossians 1:10; cf. Psalm 1:1; Ephesians 4:1). Paul’s example, that we are to follow, is that he always made it his aim to please God (2 Corinthians 5:9). And while the apostle instructs us elsewhere to “try to discern what is pleasing to the Lord” (Ephesians 5:10), here he tells us clearly one way that we know is pleasing to the Lord – “abstain from sexual immorality.”

2. This teaching about sexual purity comes from the Lord Jesus.

1 Thessalonians 4:2 – For you know what instructions we gave you through the Lord Jesus.

One of the problems today is that many in the American church want to simply assign “purity culture” to a dated holdover from previous generations. “Purity culture” is shamed and slammed. There are some aspects to previous iterations of an emphasis on sexual purity that were not helpful in the long-run, and some advocates of it who have turned out to be false teachers, but we can’t throw the baby out with the bathwater.

The command to live in sexual purity is not a teaching made up by conservatives trying to hold on to an older way of life. It’s not a teaching made up in 1960’s America as a response to the sexual revolution. It’s not a holdover from the Puritans. It’s not even something that the apostle Paul himself made up. It’s the “instructions (Paul) gave you through the Lord Jesus.” The NLT says it like this, this teaching comes “by the authority of the Lord Jesus.” It’s Jesus’s teaching. Jesus’s command. It comes with Jesus’s authority. And Jesus is Lord.

3. Sexual purity is God’s will for your life, a specific aspect of pursuing holiness.

1 Thessalonians 4:3 – For this is the will of God, your sanctification: that you abstain from sexual immorality.

1 Thessalonians 4:7 – For God has not called us for impurity, but in holiness.

When I worked in college ministry for a few years prior to attending seminary, I fairly often was asked for advice on discerning “God’s will” for someone’s life. “What’s God’s will for my life?” is a common question. And while the aim in those conversations is generally about long-term decisions, in day-to-day living God’s word is very clear: God’s will is your personal holiness.

“For this is the will of God, your sanctification,” Paul writes. And immediately after that, he moves on to one particular aspect of that: “that you abstain from sexual immorality.”

Sexual immorality is a general term that covers any form of sexual sin, not just pre-marital sex. The Greek word is porneia, from which we derive our word pornography. Any sexual intercourse outside of marriage is included, but Jesus of course quite clearly expands our understanding of sexual sin. “I say to you that everyone who looks at a woman with lustful intent has already committed adultery with her in his heart” (Matthew 5:28). Therefore, sexual immorality (porneia) and adultery (moicheo) include sins of the mind, “lustful intent.” God’s will for you is to be free from pre-marital sex. From extra-marital sex. From sexual promiscuity. From sexual encounters outside of marriage that stop just short of actual sexual intercourse. From pornography. Pornography is a sin, along with every other form of sexual immorality. And we need to keep in mind all of the other reasons below when we consider the significance of this particular sin:

4. Living in sexual immorality is living like unbelievers who do not know God.

1 Thessalonians 4:4–5 – 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;

Paul helps us understand abstaining from sexual immorality (v.3) by telling us in verse 4 that we need to know how to control our own bodies “in holiness and honor.” Notice again the call to holiness here, but also we need to see his argument in verse 5. If we do not control our own bodies, but instead give ourselves to any form of sexual immorality, we are living “in the passion of lust like the Gentiles (or “pagans”, NLT) who do not know God.”

Engaging in sexual immorality is living like those who don’t know God. And we do know God. Paul’s implied command is this: Live like believer ought to live! You are God’s child. You are a temple of the Holy Spirit. Christ dwells in you. This should make a difference in how you live.

5. Committing sexual immorality is wronging fellow believers.

1 Thessalonians 4:6 – that no one transgress and wrong his brother in this matter . . .

When you commit sexual sin, God’s word tells us that you “transgress and wrong” fellow believers. Contrary to popular belief, sexual sin is never just a private matter. You not only sin against your own body (1 Cor. 6:18), which is also sinning against Christ’s body (1 Cor. 6:15), a temple of the Spirit (1 Cor. 6:19), but you also sin against others for whom Christ died.

When you engage in these acts, you sin against the person with whom you commit sexual immorality, even if it is via pornography. And lest you argue “but that person is not a fellow believer,” it does not minimize the sin against the individual, and there are still numerous others who you are sinning against. Your spouse, or, if you are unmarried, perhaps your future spouse. Your family members. Your church members. The family members, or spouse, of the person you are watching on physically engaging with. Though committed in the dark, it is not a private sin.

6. The Lord will avenge these sins.

1 Thessalonians 4:6 – . . . because the Lord is an avenger in all these things, as we told you beforehand and solemnly warned you.

Coming right off of the previous point, there is the warning in 1 Corinthians 3:17 that we need to hear and to heed: “If anyone destroys God’s temple, God will destroy him. For God’s temple is holy, and you are that temple.” As we blatantly sin against the body in this way, we are inviting the discipline or the judgment of God, who is “an avenger in all these things.”

7. If you disregard this teaching, you disregard God.

1 Thessalonians 4:8 – Therefore whoever disregards this, disregards not man but God, who gives his Holy Spirit to you.

Finally, as with number 2, we need to remember whose teaching this is. This is not man’s teaching, this is God’s.  Speaking of God’s Word, Wayne Grudem helpfully says it like this in his Systematic Theology: “to disbelieve or disobey any word of Scripture is to disbelieve or disobey God.” If you reject this, you are not simply rejecting a teaching of the church, or a teaching of a pastor, or a teaching that the church has historically held, or even just a word from the Bible; you are rejecting God.

Hope for the Battle

Let me end with this –– Back in verse 4, Paul ties living in sexual purity to “controlling (your) own body.” We must live with self-control. But if that seems too difficult for where you are in life right now, in this struggle for you right now, remember this: self-control is a fruit of the Spirit.

The truth is, to live this way, you have to live in dependence on God, who promises you that he “is able to make all grace abound to you, so that having all sufficiency in all things at all times, you may abound in every good work” (2 Corinthians 8:9). You can do this, because he is with you. Ask him for grace for today. And then tomorrow, ask him for grace again. And the next day, and the next day. And act on the grace that he supplies, pursuing holiness and a life that is pleasing to him, the One who gave his Son for you and enables you by his Spirit to walk worthy of him.


Bert Watts has served since December 2016 as the Senior Pastor at Mountain Creek Baptist Church, where he has been on staff since 2012.

Photo by Jan Meeus on Unsplash