The first question and answer to the Westminster Shorter Catechism is huge if true (and it is). “What is the chief end of man? Man’s chief end is to glorify God and to enjoy Him forever.” That’s monumental.

Even better, though not as short, is the first Q&A in the Heidelberg Catechism, affectionately referred to as Heidelberg 1.

Q. What is your only comfort in life and in death?

A. That I am not my own, but belong—body and soul, in life and in death—to my faithful Savior, Jesus Christ. He has fully paid for all my sins with his precious blood, and has set me free from the tyranny of the devil. He also watches over me in such a way that not a hair can fall from my head without the will of my Father in heaven; in fact, all things must work together for my salvation. Because I belong to him, Christ, by his Holy Spirit, assures me of eternal life and makes me wholeheartedly willing and ready from now on to live for him.

”I am not my own.” This is not the greatest let down to self-esteem, the greatest pride-balloon pop, or the greatest discouraging word, though our humanistic culture might disagree. It is the greatest comfort. This is not merely Calvinism in the classroom, this is Calvinism as a soul-fortress. I am not my own because I have been created, and my Creator is God. I am not my own because I have been purchased, and my Savior is Lord. My body and breath are not my own, they are a gift from the will of God. And as one who has sinned and deserves death and the brutal accusations of Satan, my sins are forgiven and I have been freed from guilt and eternal punishment because of His definite atonement.

This is comfort for soul and body. Not a hair can fall from my head apart from the Father’s will. This is also motivation for righteousness for soul and body. Every hair on my head can be combed for the Father’s will.

The Heidelberg answer, “I am not my own,” is 1 Corinthians 6:19 first-personalized. While Paul has given warnings along the way, he has been driving to this all along. He has been asking the Corinthians to remember their doctrine and the implications of those truths for sake of their sexual morality.

The final part of verses 12-20 ask three “Do you not know?” questions. In verse 15, don’t they know that they are members of Christ’s body? In verses 16-18, don’t they know that they are one-d with Christ. And in verses 19-20, don’t they know that they are owned by Christ?

We finished near the end of Paul’s thoughts on being one-d with Christ last Lord’s Day. He told them that they should flee sexual immorality , which is an urgent and serious exhortation that applies to more than intercourse outside of the one man-one woman one-fleshedness in marriage. We saw an illustration (Joseph with Potiphar’s wife) and similar instruction (Solomon to his sons in Proverbs) from the Old Testament that sex sins are not sins to fight but to flee.

There is a reason given in the last part of verse 18. Every other sin a person commits is outside the body; but the sexually immoral person sins against his own body .

Someone might ask how suicide is not a sin against one’s own body. Gluttony and drunkenness also appear to cause self-fleshly inflicted wounds. But there is something in our image-bearing nature, something in our relation-reflecting being, that causes sexual immorality to hurt us in a way that other sins don’t. Sexual sins are selfish sins, but they aren’t solitary sins; it takes two to make a thing go wrong. The physical union could result in a new life, so a third person is permanently involved.

There are sexually transmitted diseases, yes (MacArthur concludes that the verse is referring to a prevalent “venereal disease” in Paul’s day). But Paul is referring to a deeper stain here. There are some consequences of sexual immorality that cannot be undone, even if they can be forgiven. These consequences are sometimes tangible, sometimes emotional, often both. So Solomon said,

He who commits adultery lacks sense;
he who does it destroys himself.
(Proverbs 6:32)

So don’t even get near. Flee sexual immorality because it ruins unlike other sins.

Owned by Christ (verses 19-20)

The final “do you not know?” question starts in verse 19.

Or do you not know that your body is a temple of the Holy Spirit within you, whom you have from God? Paul already used the temple analogy with the Corinthians. In chapter 3 he was pointing out that some preachers not only do bad work, some of them do destructive work. The church is God’s temple, the place where God through the Holy Spirit dwells, so those who attack the collective structure are attacking the temple.

In chapter 6, though, Paul presses the temple analogy not to the whole but to each member. Just as each believer is united to Christ, so each believer has the Holy Spirit within him. God Himself resides in each Christian. The Spirit is a gift from God, the one who seals our inheritance in the kingdom of God. And shall we then do unholy things with the Holy Spirit with us?

In the final part of verse 19 through verse 20 Paul advances into another reason for our sexual purity. We are united with Christ, one-d with Him. We are also purchased by Him.

You are not your own, for you were bought with a price . This is slavery language. But it is not freedom from slavery, it is freedom from a wicked master.

Our status is upgraded by this slavery. The alternative to being owned is not to be self-determined. If we can be purchased, it means that we already had an owner. Though Paul doesn’t say that Jesus paid Satan, we were slaves of sin. Christ’s purchase delivered us into a better kingdom.

“Redemption is from a state of jeopardy by a costly act to a new state.” (Thiselton)

The price was Christ’s blood. Paul already referred to the word of the cross (1:18), to Christ who is our redemption (1:30), to “Jesus Christ and him crucified” (2:2). As we approach Good Friday and Resurrection Sunday, we have our reason for holiness in our relationships. It is true that He paid the penalty for our sin, and in doing so He paid to make us His own.

The doctrine of the atonement means that your heart and your parts are designated for service. Because of Christ’s death and resurrection, if you believe, then all your sin, sexual and otherwise, is covered. Jesus absorbed God’s wrath in your place. And also, because of Christ’s death and resurrection, you are under new management. The atonement is an economic transaction. You used to go every day into the Darkness District and work for Seed of the Serpent Incorporated. Then you were bought out. But you weren’t bought out to work for yourself. You are under contract to serve a new Lord, the King of Righeousness.

The conclusion is: So glorify God in your body . We tend to think about glorifying God in our thoughts; we think that He’s great. We also think about glorifying God with our songs; we sing that He’s great. But we can bring glory to God by where we keep our feet from going, where we keep our eyes from looking, where we keep our hands from touching, and where we keep our hearts from lusting.

We serve God, or ourselves or others, by what we do in the body. As Paul said the body is meant for the Lord and the Lord for the body (verse 13). It certainly applies to whatever we do, even what’s for dinner, as a similar exhortation says later in the letter: “whether you eat or drink, or whatever you do, do all to the glory of God” (1 Corinthians 10:31). How we work, how we play, how we date, how we dress, all of those count.

“To glorify God in our body means so to use our earthly body that men may actually see that also these our bodies belong to God.” (Lenski)

The particular context is being righteous in our relationships with the opposite sex, and same sex, too.

Conclusion

There will be more about sex and marriage and divorce and remarriage and virgins and betrothal in chapter 7. We’ll get there a month from now, with Easter next Sunday, Jim preaching the Sunday after that, and Jonathan preaching the Sunday after that. But before we finish here, the issues in chapter 6 are entirely about the heart, and the parts.

I’ve gotten feedback, all of it revelatory, about my comments on various external parts, such as the example of haircuts. “Isn’t it about the heart?” Yes. And what we want will become visible, sooner or later, in one way or another. How a man thinks is why a man chooses his “look.” And how he wants to look tells something about how he wants to interact with others and be seen by them. His choices show his heart; “the tree is known by its fruit” (Matthew 12:33). How a woman seeks identity and security is visible in who she hangs out with and how she lets herself be treated. Motives get displayed.

You are not your own. You don’t get to have whatever motives you want, and you certainly don’t get to claim your motives are pure while decorating yourself with symbols of impurity, or while following the trendy mold of the world. Our emotions are not the Lord, our thoughts are not the Lord, Jesus is Lord.

I think two things relate to Paul’s connection that we are not our own with sexual purity. First, we ought to love image-bearing masculinity, femininity, and marriage a lot more than we do. In 1 Corinthians 6, the intimacy that comes with sex is precious. Let us be a people who love marriage more, get into covenant sooner, who are more serious about purity and fruitfulness. And second, we ought to have a much clearer line between married and not married than we do.

Our culture has been blurring the line of marital commitment between one man and one woman (and now between male and female), if not trying to demolish the line, for at least 50 years. But free love has not been free, and making it easier to divorce has not made anything easier. Movies and television have made sex look fun for all, and made teenage and twenty-something romance seem emotional, but mostly harmless. So many parents say about their kids, “Everyone has to experience it.” No they don’t.

When does it become the case that you are not your own? When does being the temple of the Holy Spirit kick in? Both of these happen at conversion. If you are a Christian, then you get to not be a slave to your emotions and the “passion of lust like the Gentiles who do not know God” (1 Thessalonians 4:5). Look right there: it’s a heart issue. Those who don’t know God don’t know how to control their hearts, and it becomes visible on their outsides. Those who aren’t owned by Jesus are owned by their lusts.

So it’s not “cute.” What is the reason to have a boyfriend or a girlfriend or a significant other? What is the reason to date, to go out? What benefit is there in focusing your attention and affections on one person without any promise from you or to you of faithfulness? Being married is great. It can be messy, but it is a mess worth making. But “playing” married couple, emotionally and physically, is playing with fire. We can work to get young people ready for marriage responsibilities sooner, but that’s different than letting them flirt with sexual immorality.

You are not your own. As 1 Corinthians 7 states, and as 1 Thessalonians 4 implies, you are actually your spouse’s, and if you don’t know your spouse yet, then you should wait to share your parts and your heart.

It is precisely in how a person reveals themselves as what they are in the bodily and everyday life that what it means to be “in Christ” emerges. (Thiselton)

As the point of this paragraph has been, you are not your own, you are the Lord’s. That has consequences. It is a great comfort, and it is a great catalyst to purity. So glorify God in your body.