Translators have to make judgment calls all the time. Sometimes they hit the nail on the head, and other times they don’t. Nevertheless, it’s worth noting that the job isn’t the easiest and they do their best. Let’s take one passage as an example: 1 Thessalonians 4:4
NIV: That each of you should learn to control your own body in a way that is holy and honorable.
NASB: That each of you should know how to possess his own vessel in sanctification and honor.
I would translate it as, “To know each one of you his own vessel how to acquire/possess in holiness and honor.” The term “vessel” was often used concerning a wife in antiquity because she received the seed of her male counterpart in sexual intercourse (cf. 1 Peter 3:7). Simply put, Paul may be giving instructions on acquiring and having a wife. Since the vessel was utilized as a receptacle, we see it elsewhere in Scripture: Paul was God’s chosen vessel (Acts 9:15), and indeed he received the Holy Spirit (Acts 9:17). Believers, too, were vessels meant for honorable use while unbelievers were for dishonorable use (Rom. 9:21; cf. 2 Tim. 2:20–21). The honorable were receptors of the Holy Spirit like Paul (Rom. 8:9–11) and mercy, while the dishonorable were receptors of wrath (9:23). Since her husband ruled the wife in ancient Rome, she was considered his possession. Therefore, the proper acquisition of a wife demands the husband avoid passion. One reason this interpretation is plausible is based on verse six, which discusses exploiting a brother or sister.
Passion was the dishonorable loss of self-control, according to the ancients. As one scholar put it, “Vices of excess bring shame upon those who commit them [1 Cor. 7:35-36; cf. 6:18].” The active form of decorum referred to a dignified appearance obtained through the control of elimination of all passions, particularly those relevant to drinking alcohol, overeating, and sex. Pleasures overindulged in were seen as filled with passion and ugly practices. What was Paul advocating? Paul likely encourages that men regard women as valued. Perhaps even Christian equality, friendship, and mutual openness.
This was counter to the Greco-Roman view:
For this is what living with a woman as one’s wife means—to have children by her and to introduce the sons to the members of the clan and of the deme, and to betroth the daughters to husbands as one’s own. Mistresses we keep for the sake of pleasure, concubines for the daily care of our persons, but wives to bear us legitimate children and to be faithful guardians of our households. (Demosthenes 59.122; ca. 382–322 BC)
Avoid impurity to the utmost of your power before marriage, and if you indulge your passion, let it be done lawfully. But do not be offensive or censorious to those who indulge it, and do not be always bringing up your own chastity. (Epic. Ench. 33.8; ca. AD 55–135)
While it was not unusual for Roman citizens to have multiple sexual partners, homosexual encounters, and engagement with temple prostitutes, Christians stood out precisely because of their refusal to engage in these practices.
“One in mind and soul, we do not hesitate to share our earthly goods with one another. All things are common among us but our wives” (Tertullian, Apol. 39).
“[Christians] share their meals, but not their sexual partners” (Diogn. 5.7).
Christians “do not commit adultery nor fornication” and “their men keep themselves from every unlawful union” (Aristides, Apol. 15).
In his defense to Octavius, Marcus Felix (c. third century) contrasts the sexual ethic of the pagan world with that of Christians:
Among the Persians, a promiscuous association between sons and mothers is allowed. Marriages with sisters are legitimate among the Egyptians and in Athens. Your records and your tragedies, which you both read and hear with pleasure, glory in incests: thus also you worship incestuous gods, who have intercourse with mothers, with daughters, with sisters. With reason, therefore, is incest frequently detected among you, and is continually permitted. Miserable men, you may even, without knowing it, rush into what is unlawful: since you scatter your lusts promiscuously, since you everywhere beget children, since you frequently expose even those who are born at home to the mercy of others, it is inevitable that you must come back to your own children, and stray to your own offspring. Thus you continue the story of incest, even although you have no consciousness of your crime. But we maintain our modesty not in appearance, but in our heart we gladly abide by the bond of a single marriage; in the desire of procreating, we know either one wife, or none at all (31).
Now, for argument’s sake, let’s say that he isn’t talking about having a wife. The other interpretation would be how one uses his or her own body in holiness and honor by avoiding fornication. Either interpretation is in keeping with Christian doctrine and morality. Yet, you see why some translations would prefer body to vessel.