In summary, Paul identifies in 1 Cor 6:9 male same-sex behavior as sinful. He places none of the qualifications or limitations upon that behavior for which some in recent times have pled. There is, in other words, no category of acceptable or virtuous same-sex behavior in Paul’s thinking. Paul furthermore recognizes that what may attend such behavior is the conscious blurring of culturally discernible lines between masculinity and femininity.
μαλακοὶ (malakoi) and ἀρσενοκοῖται (arsenokoitai) in 1 Cor 6:9
Paul uses two words in 1 Cor 6:9, “μαλακοὶ” (malakoi) and “ἀρσενοκοῖται” (arsenokoitai), that are as important to Paul’s understanding of sexuality as they are difficult to understand. Consider how differently leading English translations render this part of the verse.
“men who practice homosexuality” (ESV; a marginal note reads, “The two Greek terms translated by this phrase refer to the passive and active partners in consensual homosexual acts”)
“men who have sex with men” (NIV ; a marginal note reads, “The words men who have sex with men translate two Greek words that refer to the passive and active participants in homosexual acts”)
“male prostitutes … homosexual offenders” (NIV 
“effeminate … homosexuals” (NASB 1995; a marginal note to the first word reads, “i.e. effeminate by perversion”
“effeminate … sodomites” (NKJV)
“effeminate … abusers of themselves with mankind” (AV)
These translations appear to agree that the individuals in view are men who are engaged in some kind of sexual activity of which Paul disapproves. But the translations’ differences outshine their agreement. Should the terms be understood together or separately? Does the term malakos denote male homosexual activity (generally), the passive participant in a homosexual act, a man who engages in paid sexual activity with other men, or an effeminate man? Does the term arsenokoites denote male homosexual activity (generally) or the active participant in a homosexual act (specifically)? A survey of the commentaries and academic literature yields further possibilities.
What is Paul trying to say to the church? How does his teaching in this verse address the sexual landscape within and outside of the contemporary church? We will summarize what the apostle is saying in these two words in four points, and then draw four pastoral conclusions from his teaching.
Paul’s Meaning in 1 Corinthians 6:9
First, the two words malakoi and arsenokoitai describe individuals who are engaged in activity that Paul regards to be sin. We see this point in at least two ways. First, these two words fall in a much longer list in 1 Cor 6:9-10. Paul insists that persons whose lives are characterized by these actions “will [not] inherit the kingdom of God” (1 Cor 6:10). There is considerable overlap between this list and the list of 1 Cor 5:11, which describes individuals who are subject to the discipline of the church. Second, the word arsenokoitai appears in one other place in the New Testament, 1 Tim 1:10. In the context of Paul’s argument of 1 Tim 1:10, this word describes a violation of the moral law of God (“the law is not laid down for the just but for the lawless and disobedient, for … men who practice homosexuality,” 1 Tim 1:9, 10 [ESV]). These two words, then, describe activities that are violations of the law of God, that exclude one from the Kingdom, and that are subject to the church’s discipline. Paul understands these two words to describe sin.
Second, Paul understands these two words to describe a particular kind of sexualsin. These two words follow three words, two of which denote immoral sexual offenders (“the sexually immoral … adulterers” [ESV]). The word arsenokoitai follows “the sexual immoral” in Paul’s catalog of sins against the Decalogue in 1 Tim 1:10. The context in which the terms malakoi and arsenokoitai appear together, then, shows that these terms refer to a specific type of sin against the seventh commandment.
Third, these two terms together capture the range of male same-sex activity. Some have argued that Paul is only condemning a particular or narrow kind of homosexual behavior, such as prostitution, pederasty, or rape. On this reading, there is space in Paul’s ethic for non-exploitative homosexual activity between two consenting adults. This view runs aground on Paul’s argument in Rom 1:18-31 and it finds no support from 1 Cor 6:9. For one thing, in Paul’s day, the term malakos had already acquired a technical meaning when it was used in sexual contexts. It denoted the passive partner in male same-sex activity. The term arsenokoitai makes the point particularly clearly. As commentaries frequently note, Paul is the first Greek writer who appears to have used this term. It is a compound formed from two nouns meaning “man” and “bed.” Its origins are not difficult to discover. These two terms appear together in LXX Lev 18:22 and 20:13. In fact, in Lev 20:13 the two component parts of Paul’s new word stand side by side. Both these passages in Leviticus roundly and categorically condemn same-sex activity. This background is important to understand what Paul means by the term arsenokoitai. This word must refer to a wide range of male same-sex activity and may properly be translated “bedders of males, those [men] who take [other] males to bed,” “men who sleep or lie with males.” Since it is paired with the word malakoi, the word arsenokoitai may particularly denote the active partner in male same-sex activity. The two terms, malakoi and arsenokoitai, then, capture, in unqualified and comprehensive fashion, male same-sex activity.
Fourth, Paul is concerned to address sinful sexual behavior in these two terms, but not only such behavior. In Paul’s day, the term malakoi could denote more than just sexual activity. Such persons sometimes “intentionally engage[d] in a process of feminization to erase further their masculine appearance and manner.” That is to say, the word malakos was used to describe “a man who is trying to be a woman,” a man “who significantly blur[s] gender distinctions.” To be sure, Paul’s primary concern in 1 Cor 6:9 is with same-sex behavior. But the apostle is also aware that, in the social context of which he and his readers were part, those who committed themselves to this lifestyle not infrequently blurred the culturally discernible lines between a man and a woman. It is in this sense that one can appreciate the translation “effeminate” for malakoi, even if one opts for another English word that better captures the sense of the Greek word in the context of Paul’s argument.
See the discussion particularly of Robert A. J. Gagnon, The Bible and Homosexual Practice (Nashville: Abingdon, 2001), 303-39; S. Donald Fortson III and Rollin G. Grams, Unchanging Witness: The Consistent Christian Teaching on Homosexuality in Scripture and Tradition (Nashville: B&H Academic, 2016), 277-301; and David E. Garland, 1 Corinthians, BECNT (Grand Rapids: Baker, 2003), 212-5.
The term is a substantival adjective meaning “soft.” Greek writers used this adjective in both non-sexual and sexual contexts.
See the literature cited at BDAG, “μαλακός,”and Gagnon, The Bible and Homosexual Practice,306-12.
LXX Lev 18:22 reads καὶ μετὰ ἄρσενος οὐ κοιμηθήσῃ κοίτην γυναικός βδέλυγμα γάρ ἐστιν. Lev 20:13 reads καὶ ὃς ἂν κοιμηθῇ μετὰ ἄρσενος κοίτην γυναικός, βδέλυγμα ἐποίησαν ἀμφότεροι·θανατούσθωσαν, ἔνοχοί εἰσιν.
Gagnon, The Bible and Homosexual Practice, 312.
Ibid., concluding a discussion of 1 Cor 6:9 and Philo Spec.Leg. 3.37-42.
Preston Sprinkle, People To Be Loved: Why Homosexuality Is Not Just An Issue (Grand Rapids: Zondervan, 2015), 107, 118. He prefaces the statement on p. 107 by saying that the term malakoi “as it stands alone … probably refers to effeminacy in the Roman sense.”
See Paul’s express concern for this matter, albeit in a different context, at 1 Cor 11:2-16, Gagnon, The Bible and Homosexual Practice,328.