This paper is what I presented at the recent Laidlaw-Carey/Otago sponsored colloquium on theological interpretation. If you've already read my thesis, there is nothing new here, but if you haven't will give you a skeletal version of my last chapter. Enjoy!
In warning the Corinthians against πορνεία, sexual immorality, Paul does not appeal to OT law or the ruling of the Jerusalem council (Acts 15:20, 29) instead he gives a stricter indictment against prostitution than anything found in the OT. David Horrell argues that Paul’s argument here is based on the “presumption” that sex with a prostitute is illicit, while sex with a spouse, believing or not, is permitted. He claims that, “while Paul uses arguments about holiness and bodily union with Christ to support and promote his sexual ethics, the substantive ethical convictions themselves are not derived from these arguments but are already assumed.”
In Horrell’s reading Paul is using the theological indicative only to support a previously assumed moral imperative. The ethical motivation is theological but the ethical content is merely conventional. On the other hand for Karl Barth, in 1 Cor 6:18, “Paul is speaking of a sin of which only the Christian is really capable.” That is, not only is the ethic not conventional, but even the sin is not conventional! Horrell and Barth cannot both be right.
My argument then is this
There were both Jewish and pagan objections to the use of prostitutes, but Paul’s argument does not resemble those nor show any concern in whatever ways prostitution might have been generally viewed as immoral. Although 1 Cor 6:12 does read in many ways like a general argument from benefit and permission, using the language of similar pagan arguments, Paul expands those principles in vs13-20 in a way that could only apply to the Christian. He does not describe social, moral, or material consequences, norms, or ideals. Instead the command to flee πορνεία is located solely in the Christian’s relationship to God through Christ in the Spirit.
At stake is whether Paul’s ethic is truly theological in content or merely conventional? All of which is to beg the question, what exactly was the conventional morality?
So, what was Conventional Morality?
Paul is certainly not the only moralist of antiquity to exhort against prostitution, however, such exhortations were rare. Given that prostitution was ubiquitous throughout the Greco-Roman world it receives surprisingly little attention for something that was a morally questionable act. 1st cent. Jews found prostitution one repugnant example among many of gentile sexual immorality  and a well worn metaphor to condemn idolatry.
Josephus provides a significant Jewish parallel, in Ant. 4.8.9/§206. There, in his retelling of Deut 23:18 (v.19 LXX), the Israelites are told,
From the hire of a prostitute let no sacrifices be paid; for the Deity has no pleasure in naught that proceeds from outrage, and no shame could be worse than the degradation of the body. Likewise, if one has received payment for the mating of a dog, whether hound of the chase or guardian of the flocks, he must not use thereof to sacrifice to God. (Thackeray)
Here, The wages of a prostitute are compared to the price given for the servicing of a bitch, and both are deemed unsuitable for offering sacrifices to God. The profits from selling sexual intercourse, whether human or canine, are tainted with the shame of that intercourse (τοῖς σώμασιν αἰσχύνης).
It is interesting that Josephus does not condemn the owning or use of prostitutes or dogs, only the use of profits from their sexual activities for sacrifices. The uncleanness of the sex act attaches itself to the money made through it. In the case of the dogs, the shame does not spread to the sheep they keep, the game they catch, or its owner. In the same way, Josephus gives no indication that the shame of prostitution affects those who own or use prostitutes – only the prostitute bears the shame.
The only contemporary sustained treatment is in Dio Chrysostom’s 7th Discourse (7:133-37). Chrysostom’s target is those who rule the city (7:136-7) and his concern the way in which they deal with the “brothel keepers” (πορνοβοσκῶν, 7:133). In line with some other Greek moralists he considers that sex should be reserved for marriage and even then only for procreation (7:134-5) (compare that to Paul’s attitude in 1 Cor 7). Chrysostom considers it wrong to profit by human misfortune, assuming prostitutes to be slaves by either war or purchase (7:133; cf. 7:52). He refers to the “hapless women and children” involved as σώματα (7:133), exploiting them is beneath the dignity of any moral man. Such sexual activity outside of a productive marriage is a source of shame (αἰσχύνω) and constitutes disrespect of the gods (7:133-5, cf. 1 Cor 4:14; 6:5). Although much of Chrysostom’s treatment is humane, ultimately his concern is with the effect unrestricted prostitution has on the overarching morality of the city (7:140-52; cf. 1 Cor 5:6-13). The holiness that is potentially defiled is not that of the individuals involved but of the “government buildings and temples” (7:133-4). Moreover, his injunctions are not absolute; the city rulers must moderate their response to prostitution according to what is “practicable” (7:137).
In both examples there is a focus on the shame of sex and in both the prostitutes are referred to as σῶμαta, a word which when referring to the human body emphasised objectification. We see how hard it would be to define a conventional ethic of prostitution, but that if we did both Jews and Greeks would focus on criteria of shame and consider the prostitutes as objects, somata, on which the male moral agents acted.
And so we return to Paul and 1 Corinthians
1 Cor 5:1 is evidence that Paul is aware of conventional pagan morality; however, such morality is not regarded as a standard for the community so much as a mark of how far the community has fallen short. On the other hand, in arguing against prostitution in 6:12-20 Paul does not draw on a wider morality. In contrast to Dio Paul shows no concern for the effect of prostitution on the rest of the church community (cf. 1 Cor 5:1-13) or for what is “practicable,” his command to “flee sexual immorality” (6:18a) leaves no room for compromise or negotiation.
Instead, the weight of the argument in 1 Cor 6:12-20 comes from shared convictions (or what Paul hopes are shared convictions) that are theological in nature. The threefold occurrence of οὐκ οἴδατε “do you not know!” is a rhetorical device that serves to mark those shared convictions: membership of Christ (6:15), the nature of marriage as an order of creation as taught by Gen 2:24 (6:16), and the believer’s inhabitation by the Spirit (6:19). Additionally, by the same token, οὐκ οἴδατε occurs in 6:2 and 6:9 showing that eschatological expectation is another shared conviction on which Paul can lean, and he does so in 6:13-14.
Furthermore, the “diatribal style” that Paul uses here, often used “in philosophical schools to portray mistaken inferences,” argues in favour of the fact that the visiting of prostitutes is a consequence of incorrect ethical inferences from the theological principle of Christian freedom. 1 Cor 6:12-20 presents itself as a corrective working from that principle of freedom in vs12 to the ethical result of avoiding πορνεία in vs6:18. Paul certainly appears to be trying to demonstrate a theological rational for his ethic, but does this reveal or conceal its true source?
Paul’s logic begins in 6:13 with God, who will be the one to bring history to its end, demonstrating responsibility for its event and course (1 Cor 6:13). God’s re-creative power displayed in the resurrection of Christ will ultimately accomplish the resurrection of the dead (6:14). The expectation of God’s raising of the dead is so fundamental to Paul’s understanding that he is able to state in 1 Cor 15:34 that those who deny it have “no knowledge of God”. This eschatological fact defines not just the telos of history but also of every body destined for that resurrection.
In v16 the citation of Gen 2:24 grounds the argument in the order of creation and thus θεός as creator. The re-creative power which raises the dead has the same source as the creative power that shaped man from the mud, breathed life into him, and formed woman from the man’s rib (Gen 2:7, 21-25). God’s creative ordering of male female relationships within the marriage covenant and the human body as object of God’s eschatological resurrection are both denied when the unifying aspect of sex is ignored and a human being made in God’s image is treated as a commodity to satisfy an appetite.
In v20 the final indicative statement of the pericope is to affirm the believer’s possession by God in the present. In Gal 5:1 Paul had described the Christian’s relationship to God in terms of the ransom of a slave or prisoner. In the Greco-Roman world, once set free, a ransomed slave remained heavily indebted to their benefactor. Thus the freedom granted in Christ also creates a responsibility to Christ. In Galatians Paul wants to encourage the use of freedom in opposition to dependence upon the law, in 1 Cor 6:12-20 the image is of a transfer of ownership because he is encouraging the voluntary restriction of freedom in respect of the one who has granted that freedom. The price Paul refers to in v20 is of course the death of Jesus Christ, which has brought them freedom and so obligated to God, over and above their relationship to God as creator and judge. God’s saving action in Christ is thus revealed as a “fundamental motivation of Paul’s ethics.”
So as the believer’s relationship with Christ is taken into account that the argument begins to take on a specifically Christian character.
In 1 Cor 10:23-11:1 Paul’s second and longer exposition of πάντα ἔξεστιν “everything is permitted” concludes with the injunction to imitate Paul’s imitation of Christ. The avoidance of domination, of giving an unqualified other authority over your body, is important (6:12) but it is not an abstract freedom, it is a freedom from and a freedom for. Nevertheless, the Christian’s experience of freedom is constrained primarily by the need to seek the advantage of others (σύμφορον, 6:12; 10:33). Given how important the consideration of others for the purpose of their salvation (σῴζω) is in 1 Cor 10:28, 33, it may be asked whether Paul shows no concern for the prostitute, her advantage and salvation, in 6:12-20.
In 6:14 Paul makes a switch from using “body” to “us”. Interpreters have sometimes missed that the correlation in Paul’s parallelism is between body and food, not between body and stomach. This is perhaps indicative of a wider assumption that the body or σῶμα refers in this instance to the target of Paul’s diatribe. However it may make as much, or even more, sense to see the σῶμα as the object of the appetite of πορνεία, just as the food is the object of the stomach’s appetite. This reading gives full weight to the parallelism found in 6:13-14. If that is the case, Paul’s objection to the use of the σῶμα for πορνεία, instead of for the Lord, is not only his objection to the use of the believer’s body for the satisfaction of the appetite, but also to that use of the prostitute’s body.
We have no reason to assume that the σῶμα in 6:13 is exclusively the male believer’s, except that it has consistently been interpreted this way by men. Although in v. 13 the definite article with each use of σῶμα is masculine, if it was meant to include both male and female, that is the form it would take. Although it is in singular form, Paul uses σῶμα as a distributive singular elsewhere and so could be doing so here. From a man’s point of view it is natural to assume that Paul’s is concerned with the man’s destiny, but σῶμα “body” was often be used to refer to slaves and objects of sexual desire, and a prostitute was usually both. In both the significant parallels of Dio Chysostom and Josephus, it is the prostitutes that are referred to as σώματα, not the men. It is a plausible suggestion, then, that Paul expects his readers to understand σῶμα as referring to both πορνεύων and πόρνη, both prostitute and client. Paul’s argument in 6:13-14 could then be paraphrased thus: we will be raised, so by what right do we treat another body as if she will not, as disposable property, as something that has no stake in eternity, like mere food?
The feminist biblical scholar Angela West has rightly shown how traditional interpretation of this passage neglected the exploitation of the woman in the act of prostitution. It may be, however, that Paul’s concern is more explicit than that and has only been hidden by a failure to allow σῶμα its polyvalence as potentially referring in 1 Cor 6:13-14 both to the abused and the abuser. In 6:15 Paul then specifies that “your bodies” are members of Christ as opposed to using the inclusive “the body” of 6:13.
Concern for the other body, the prostitute, can be seen as a consequence of a desire to imitate Christ and to follow his teachings in general. We read in 7:10 that Paul’s view of marriage is self-consciously derived from Christ’s teaching on the subject, but Paul’s argument in 6:16-17 assumes that marriage confers authority on each partner over the other’s body (7:4), which is a totally unconventional suggestion in both Jewish and Greek thought, could well be a development of Jesus’ teaching on divorce found in the gospels (Matt 5:31-2; 19-1-9; Mark 10:1-12) which profoundly redefined Jewish teaching on marriage and adultery, as William Countryman writes, Jesus “not only forbade the man to divorce his wife, but also gave her a permanent and indissoluble claim on him as her sexual property.”
In 1 Cor 6:15 Paul’s concern is revealed to be the believer’s union with Christ. We havenow uncovered two ethical reasons why using the prostitute violates union with Christ, firstly because it fails to imitate Christ’s concern for the other’s salvation and secondly because it fails to apply Christ’s teaching on marriage. For Paul, union with Christ is thus practised and maintained in the believer’s ethical life through the imitation of Christ and adherence to his teaching.
The assertion in 6:15 that the believer’s unity with Christ can be broken through actions which contradict it argues that Christ’s saving work is not yet complete. Thus, the Corinthian believer exists in a liminal state for which the desert wanderings of Israel in the OT are paradigmatic as Paul explains in 1 Cor 10:1-13. A “carelessness” about ethical conduct, resulting from an over confidence in their new status in Christ, puts them in danger of suffering “divine rejection.” Paul is concerned to reorient the Corinthians’ eschatological map, hence Paul’s extensive presentation of the resurrection hope in ch.15. The resurrection of the body is the fundamental landmark of the future against which the Corinthians are to locate their present. 
It is this salvation historical tension that generates the connection and conflict between indicative and imperative. What has been started by Christ will only be brought to completion if the believer remains united with Christ (cf. Phil 1:6; Gal 3:3), otherwise they may very well “have come to believe in vain.” Consequently in 1 Cor 6:12-20 the use of prostitutes constitutes for the believer not just a denial of their present relationship to Christ but also a potential forfeiture of their ultimate salvation.
The ethical motivations of God as creator and eschatological judge, the generative norms of Christ’s teaching and life and the necessity of right living for the maintenance of salvation would, on their own, only produce a legalistic framework for the believer’s ethical performance. Paul’s theological ethic in 1 Cor 6:12-20 contains, however, one further vital strand, the Holy Spirit.
6:14 probably contains an implicit reference to the Spirit. In 6:17 This second reference to the Spirit, is primarily intended to explicate the nature of the believer’s union with Christ rather than make a statement about the Spirit per se. Nonetheless, unity of Christ and believer is for Paul always a function of the Holy Spirit.
The only explicit mention of the Spirit in 1 Cor 6:12-20 is in 6:19. It is preceded by the third οὐκ οἴδατε of the pericope. Against the πορνεύων, who sins into his own body, God gives the Holy Spirit who inhabits the body. The indwelling of the Holy Spirit did not render Corinthian bodies of no account but, on the contrary, gave their σῶμα special significance as the Spirit’s temple.
In 1 Cor 13:1-3 Paul makes the surprising assertion that ethical or miraculous action without “love” is “nothing.” In Rom 12:1-2, the “new moral life” requires the discernment made possible by a renewed mind rather than “simple conformity to a blueprint provided by external law or sanction.” In Gal 5:16-26 we read how behaviour stems from one of two apocalyptic powers, the flesh and the Spirit and the works of the flesh are evil in and of themselves because of their source. Paul’s consistently shows himself concerned with the source of behaviour rather than adherence to rules.
The Corinthians’ misunderstanding of the relationship between Christ, the Spirit, and their bodies, has resulted in their failure to use the Spirit as a source for their ethical actions. Yet another way in which Paul’s sexual ethic is not “conventional.” Paul has no desire to see the Corinthians try harder to be moral, burdened by a strict ethical code. Instead he wants to see them orientating their lives according to the reality of the God given Spirit. With the twin commands of “flee fornication!” and “glorify God in your body,” Paul is calling the Corinthians to realise in their behaviour the fact of Christ’s saving work past, present, and future, as evidenced by the gift of the Spirit.
Thus the presence of the Spirit in the body not only mandates a bodily life that glorifies God but enables it. The Holy Spirit is not primarily an ethical burden but ethical empowerment. Importantly, this enabling varies from person to person. In 1 Cor 7:7 we see that Paul considers the ability to remain celibate a “particular gift” from God. The assumption of 6:18-20 is that fleeing fornication is not a “particular gift” but one given to all believers.
From this pneumatological perspective we are now in a position to suggest a solution to the problem of why,
. . . according to 1 Cor 6:12-20 the close and sinful relationship of a believer to an unbeliever cancels membership in Christ and the church; according to 1 Cor 7:12-16 the close and legitimate relationship of a believer to an unbeliever draws the unbeliever into membership in Christ and the Church.
David Horrell’s argument really rests upon the apparent arbitrariness of this distinction. The assumption is that Paul is obsessed with the boundaries of the Christian community being preserved from outsiders, in 1 Cor 7:12-16 the unclean relationship with an unbeliever is only legitimised through the sanitising and stabilising effect of marriage. However Paul shows no concern that the prostitute is an outsider to the community and she could very well have been a member of the community herself. Prostitutes were usually slaves, and there were certainly slaves in the Corinthian church (cf. 7:21).
Alternatively David Garland suggests that the nature of the unions allows the transmission of different effects, thus the unclean union with a prostitute transmits uncleanness while the holy union of marriage allows holiness to be transmitted.
Nevertheless, for Paul the two relationships are not equal: Firstly, in 7:12-16 sanctification of spouse and children does not necessarily result in salvation, but in 6:12-20 union with Christ results in salvation and removal from him causes the reverse. Secondly, in 7:12-16 the sanctification through marital union does not operate through sex but only “homelife.” If we see sexual and marital union as channels for transmission of holiness or uncleanness we are forced to admit that the effect of marriage is much weaker than the effect of fornication, despite marriage being God ordained (Gen 2:24, 1 Cor 6:16) and fornication being “of the flesh” (Gal 5:19).
But if Paul’s concern is not with the transmission of holiness or uncleanness but with the source of the behaviour that forms those unions then the problem disappears! The relationship with the prostitute results in the believer’s disconnection from Christ because the source of that behaviour is not the Spirit but the flesh. The relationship of the believer to her unbelieving spouse and children generates holiness because the source of that behaviour – peacefully remaining in marriage – is the Spirit, whose fruit is peace (1 Cor 7:15; Gal 5:22). Thus for Paul the distinction between marriage to an unbeliever and sex with a prostitute is not a “presumption” imbibed from the “conventional morality” but a theological distinction based on what Paul perceives to be the apocalyptic sources of the different behaviours.
3.3.6 Conclusion: An Unconventional Ethic
To conclude, I have attempted to show how despite the difficulty of establishing a conventional ethic of prostitution, a theological reading of Paul’s ethic in 1 Cor 6:12-20 demonstrates that Paul’s ethic is not just theological in motivation but also derives its norms from the theological reality of the Christian’s relationship to God through Christ in the Spirit. Contrary to Horrell and in agreement with Barth, not only is the ethic described in 1 Cor 6:12-20 uniquely Christian, so is the sin – in this way it is decidedly unconventional.
 Roland Allen, Missionary Methods: St. Paul's or Ours? (Grand Rapids, Mich.: Eerdmans, 1962), 114.
 Rose Wu, “Women on the Boundary: Prostitution, Contemporary and in the Bible,” Feminist Theology 10 (2001): 69-81, 75.
 Horrell, Solidarity and Difference, 149, also 163-65.
 Horrell, Solidarity and Difference, 149.
 Barth, Church Dogmatics, III:2:307; also Bultmann, “The Problem of Ethics in Paul,” 213.
 See §2.1.
 See Diodorus Siculus, Bibliotheca Historica 12.21.2; Atemidorus, Oneirocritica 1.78; Aulus Gelius, Noctes Atticae 9.5.8; 15.12.2-3; Titius Livius, Ab Urbe Condita Libri 23.18.12; Plutarch, De Liberis Educanis 7, 2; Moralia 1AB, 5C; cited in Craig S. Keener, “Adultery, Divorce” pp.6-16 in DNTB, 11; Plutarch, does, however, allow extramarital sex of other varieties, Moralia 140B, and Cicero defends the use of prostitutes by young men, Pro Caelio 20.48, see Garland, 1 Corinthians, 227. Plutarch’s defence of extramarital sex does not seem to contradict his negative comments regarding prostitution, pace Garland.
 See e.g. J. Edward Ellis, Paul and Ancient Views of Sexual Desire: Paul's Sexual Ethics in 1 Thessalonians 4, 1 Corinthians 7 and Romans 1, LNTS 354 (London: T&T Clark, 2007), 41, 45, 49, 55, 62, 66, 71, 87; William Loader, The Dead Sea Scrolls on Sexuality: Attitudes Towards Sexuality in Sectarian and Related Literature at Qumran (Grand Rapids, Mich.: Eerdmans, 2009), 14-15, 48-49, 57-58, 142; Keener, “Adultery, Divorce,” 11.
 See Gen 34:31; Lev 19:29; Deut 23:18; Prov 6:26; 23:27; Sib. Or. 5.388; Ex. Rab. 43:7; Num. Rab. 9:24; 20:7; 1QS 4:10; CD 4:17; 8:5; see also Keener, “Adultery, Divorce,” 11.
 E.g. 2 Chron 21:13; Isa 23:16; Jer 3:3; Ezek 16:1-52; Hosea; Mic 1:7; Nah 3:4;
 Dio Chrysostom, Dio Chrysostom: Discourses 1-11, trans. J.W. Cohoon, LCL 257, (1932), 364-65.
 Cf. Malherbe, Moral exhortation, 152, 154.
 The absence of any discussion of procreation in 1 Cor 6:12-7:40 is a noticeable lacuna in Paul’s sexual ethics there and NT ethics generally.
 Barrett, The First Epistle to the Corinthians, 121; Contra Horrell, Solidarity and Difference, 164.
 Cf. Gupta, “Which Body is a Temple?,” 527.
 Wayne A. Meeks, The Origins of Christian Morality: The First Two Centuries (New Haven, Conn.: Yale University, 1993), 132.
 Thiselton, The First Epistle to the Corinthians, 1256-57.
 Barth, Church Dogmatics, III:305-07.
 Countryman, Dirt, Greed, and Sex, 183.
 Schrage, The Ethics of the New Testament, 10.
 See §2.6.3.
 Ibid., 282.
 Garland, 1 Corinthians, 229.
 Thiselton, The First Epistle to the Corinthians, 795.; cf §2.1.3
 See §3.2.3 above.
 See §2.2.7.
 Cf. 1 Cor 6:18, 20; 2 Cor 4:10; Rom 8:23; Fee, The First Epistle to the Corinthians, 263, n. 65; also §2.6.2.
 See §1.3.5, §2.2.7, and §3.2.2.
 Dio Chrysostom, Dio Chrysostom: Discourses 1-11, 7:133, p364.; Jospehus, Ant. 4.8.9; See above, §3.3.1.
 West, “Sex and Salvation: A Christian Feminist Bible Study on 1 Corinthians 6:12-7:39,” 72-3.
 Countryman, Dirt, Greed, and Sex, 171.
 Oropeza, “Apostasy in the Wilderness,” 77.
 Fee, God's Empowering Presence, 83.
 Now I would remind you, brothers and sisters, of the good news that I proclaimed to you, which you in turn received, in which also you stand, through which you are also being saved, if you hold firmly to the message that I proclaimed to you – unless you have come to believe in vain. (1 Cor 15:1-2)
Neither is this tension unique to 1 Corinthians. In Rom 5:9-11, for example, Christ’s work in justifying and reconciling the believer to God is juxtaposed with a future salvation from God’s wrath in Christ. In Gal 5:16-21, the Galatians, though set free by Christ, still need to be warned to avoid the work of the flesh if they are ultimately to inherit the kingdom of God.
 Schnabel, “How Paul Developed His Ethics,” 274.
 As argued in §2.4.4.
 Rom 8:2, 9; 9:1; cf. 1 Jn 2:27; 3:24.
 Thielicke, The Ethics of Sex, 45.
 Byrne, Romans, 364; also Schnabel, “How Paul Developed His Ethics,” 275-76.
 Martyn, Galatians, 493-501.
 Betz, Galatians, 283.
 Schnabel, “How Paul Developed His Ethics,” 296; see also §2.6.4.
 Furnish, 1 Thessalonians, 2 Thessalonians, 93; Malherbe, The Letters to the Thessalonians, 235.
 Ernest Best, One Body in Christ: a study in the relationship of the Church to Christ in the epistles of the apostle Paul (London: SPCK, 1955), 77-78.
 Horrell, Solidarity and Difference, 148-49; Neyrey, Paul, in Other Words, 114-29; Martin, The Corinthian Body, 163-69.
 Garland, “1 Corinthians,” 235.
 Gundry, Soma in Biblical Theology, 68.
 Ibid., 238-39.