Stewards of Holiness and Honor
In this passage, Paul exhorts the Thessalonians to steward their bodies and those of others with holiness and honor. The passage emphasizes personal responsibility for what one does sexually with one's body. Paul calls his readers to steward their morality. Bible scholar F.F. Bruce (1910-1990) expounds on this passage.
Perhaps there was no sphere of life where there was a greater divergence between Christian and pagan ethics than this. [The Thessalonians] had already received some instruction about this from Paul and his companions, and that instruction had been enforced by the personal example of the missionaries; but further insistence on sexual purity is judged advisable (possibly because Timothy's report had indicated there was some necessity for it)! Only thus could they rise above the pagan standards of sexual morality which surrounded them and lead lives worthy of their Christian confession. License in this sphere of life was a breach of the law of love to one's neighbor; and when the writers urge '[no one should wrong his brother to take advantage of him]' (v.6), they evidently envisage an offense of this kind against a female member of the household of a fellow Christian. But such license is also an offence against God, who has called his people to lives of holiness and has given them the Holy Spirit to enable them to fulfill this purpose.
Unlike some of the people of that day (and ours), who see the body and spirit as separate entities, Paul taught that sexuality is a matter of body, mind and heart. His teachings echo the teachings of Jesus. Evangelical theologian and spiritual writer in the Quaker tradition Richard J. Foster elaborates.
Jesus had a high view of sex. The Scribes and Pharisees taught that as long as you stayed away from adultery you were okay. But Jesus saw beyond the externalities of the law to the internal spirit in which people live. '[I tell you that anyone who looks at a woman lustfully has already committed adultery with her in his heart]' (Mt 5:28). Lust produces bad sex, because it denies relationship. Lust turns the other person into an object, a thing, a nonperson. Jesus condemned lust because it cheapened sex; it made sex less that it was created to be. For Jesus, sex was too god, too high, too holy to be thrown away by cheap thoughts.
Theologian and ethicist Daniel R. Heimbach minces no words in his assessment of the rampant promiscuity that has so treated today's Western culture.
[Western culture is] facing a crisis as catastrophic as thermonuclear war, and of the challenges we face, none is more consequential or demanding than the moral conflict over sex. While this conflict does not use weapons of material mass destruction, it does use massively destructive moral ideas - ideas so deadly they threaten the survival of our civilization. And yet because it concerns morality, not munitions, most evangelicals seem oblivious to how serious this crisis has become.