“You are not your own, for you were bought with a price. So glorify God in your body” (vv. 19–20).
In our day, sexual activity has been severely cheapened in the West. Instead of a precious gift meant to help cement the lifelong union of a man and woman in marriage, sexual intercourse is now something to be engaged in with a wide variety of sexual partners. As such, it can be easy for Christians to forget that sexual union is such a weighty thing. In reality, the sexual union of man and woman is so profound that it involves the two becoming one flesh (Gen. 2:24). The act itself, in all its physical and emotional aspects, vividly portrays and enacts the union of two complementary partners so strongly that we speak of marriages as consummated only after husband and wife come together sexually. Scripture views marriage and the bond it creates—including the sexual bond—as so important and union-producing that it likens the Christ-church relationship to the husband-wife bond (Eph. 5:25–33).
Consequently, God’s Word never allows us to take sexual activity lightly. In fact, Scripture views the transgressions of sexual boundaries as especially heinous, worse in their effects and deserving of more severe punishment than most other sins (see, for example, Lev. 18; 20:10–21; Rom. 1:26–27). Understanding all these things that the Bible says about sex is vital for understanding Paul’s teaching in today’s passage. The Apostle notes that sexual immorality is a sin against one’s own body whereas other sins are committed outside one’s own body (1 Cor. 6:18). Other sins besides sexual immorality are bad, of course. However, other sins do not actually join one physical body to another physical body and thus use for sinful purposes that which God designed for right and good purposes. Sex involves the whole person, body and soul, in ways that other activities do not, and it is therefore incompatible with who we are in Christ to involve ourselves so intimately with sexual immorality. The ramifications are extensive, and human experience demonstrates this. Illicit sexual activity—including fornication, homosexual behavior, pornography, and so on—is particularly enslaving and very difficult to resist once people start engaging in it.
Moreover, sexual immorality reflects a failure to understand who owns us. Believers are temples of the Holy Spirit, and His temple must not be defiled (v. 19). We have been purchased from slavery to sin by the blood of Christ. He is our gracious, generous, and holy Master, so we must serve Him by striving for sexual purity (v. 20).
Coram Deo
Sexual immorality, no matter the form it takes, is not the unforgivable sin. There is grace and mercy for all who turn to Christ, and He will never turn away anyone who comes to Him in faith. Nevertheless, sexual immorality is nothing to take lightly or to dabble with. It has devastating effects both individually and communally. If we are in Christ, we are members of His body. Thus, we dare not join ourselves to any other by committing sexual sin.