The passage
      v12. In verses 12, 13 and 18b, Paul quotes slogans used by his opponents and then details an argument against them. In the opening verse he notes that it is true that in Christ we are free from the constraints of the law, sin and death. Such freedom is beneficial. Yet, freedom can be used in a way that is not beneficial. So, we can use our freedom to place ourselves in slavery again, to be "mastered" by something or someone. Clearly, Paul has in mind "fornication" - physical sexual union with someone outside a marital relationship, in particular, visiting prostitutes. Not only is fornication an enslavement to sin, but it is an enslavement to the sexual partner. Each is psychologically imprinted onto the other. We were not set free to become a slave of sin.
      v13-14. Another false claim made by some of the Corinthians relates to an assumed dichotomy between our spiritual eternal being, and our "body", our humanity - the living, breathing, self. Some of the church members obviously put great trust in the slogan "food for digestion and the digestive system for food, and God will do away with both of them" - implying that the functions of the body, including sex, are of matters of the flesh and of this age, and therefore, unimportant. Not so, argues Paul. We have been raised with Christ, intimately united to Christ, such that our new self is certainly not for fornication. We are being transformed into the likeness of Christ and fornication is totally incompatible with that transformation.
      v15. Paul now theologically tackles the issue of fornication. He points out that the Corinthians have failed to understand the true nature of sexual intercourse. Based on Gen.2:24, "one flesh" idea, Paul explains that an integral union is established between a man and a woman in the sex act. Yet, there is also an integral union that exists between Christ and the individual believer. Thus, if the sexual union is illicit, say with a prostitute as here, then the two unions become mutually exclusive.
      v16-18a. Paul extends the point made in v15. In simple terms, the believer already belongs to Christ and is indwelt by the Spirit, how then can we go off and belong to a prostitute? The two unions are irreconcilable because they are mutually exclusive. So, avoid fornication like the plague.
      v18b. Paul now quotes another slogan: "Every sin that a person commits is outside the body", NRSV, ie. sin does not affect the true self ("other" is not in the Greek). Paul treats this slogan with disdain. Of course sin affects the self and this is easily demonstrated when it comes to fornication. Fornication "attacks" the self, psychologically imprints the prostitute onto us and tears us away from Christ. Because Christ is intimately united to us, transforming us into his image, there is a sense where our body now belongs to him; we are one with him. Sin tears at our union with Christ.
      v19-20. Since our real self belongs to God, we must glorify God in the way we treat the self. We are the sanctuary of the Spirit in the sense that we are intimately associated with the divine. This being the case, we are not a free agent. This state of grace was gained at great cost. Christ died for us "therefore honor God with your bodies."

Do your own thing
      In our passage for study, Paul has argued against fornication. He has done so, not by demanding that his readers keep the law. He has not even mentioned the law of adultery. Rather, he has reminded his readers of their standing in Christ and thus of the incompatibility of such sin with their Christian walk. A person united to Christ cannot countenance union with sin. The two are mutually exclusive.
      By being united with Christ in his death and resurrection we "have been released from the law so that we serve in the new way of the Spirit, and not in the old way of the written code", Rom.7:6. "Now that we have been set free from sin and have become slaves to God, the benefit we reap leads to holiness, and the result is eternal life", Rom.6:22 (we/you). "Therefore, do not let sin reign in your mortal body so that you obey its evil desires. Do not offer the parts of your body to sin, as instruments of wickedness, but rather offer yourselves to God, as those who have been brought from death to life; and offer the parts of your body to him as instruments of righteousness. For sin shall not be your master, because you are not under law, but under grace", Rom.6:13-14.
      It is not possible to follow Christ and then claim the freedom to sin. We will always fall short of the glory of the living God; imperfection will always be with us. Our past may haunt us, our marriages may fail, our unregenerate nature may repeatedly raise its ugly head, but God's mercy in Christ will constantly cover us. Yet, if we set our face against God and devalue the horror of sin, defiantly disregard sinful behavior, we will end up a slave to sin. Therefore, in the strength of the Lord, we must flee immorality. Through his death and resurrection we are one with him and indwelt by him. This reality will strengthen us, it will empower us to stand against temptation.
      The Christian today is constantly tempted to compromise on sexual matters. Our society is obsessed with the freedom of sensual self-expression. Yet, such freedom can only lead to slavery. So, stand in Christ.

v12
      Given that the "everything is permissible" is probably a libertine slogan, quotation marks should be added with an added introduction, "some of you say", CEV.
      exestin (ex-eimi) "is permissible" - it is possible, right. "All things are lawful", NRSV etc., is misleading since the slogan claims authority to act independently of any law or convention, so "I am free to do anything", Thiselton, Zerwick...
      sumferei (sumferw) "is beneficial" - is better, an advantage, helpful. "Not everything is profitable or expedient for the Christian life", Bruce.
      ouk egw exousiasqhsomai (exousiazw) fut. pas. "I will not be mastered" - I will not be enslaved, ruled over, bound as by a yoke. Unfettered liberty enslaves. "I will not allow anything to get the mastery over me", Bruce.

v13
      Another slogan requiring inverted comers, although the quote probably includes "and God will do away with both of them", Barrett, Thiselton.... Obviously the slogan includes all bodily functions, particularly sex. Paul would generally agree on the food issue, but even here it is necessary to be all things to all men, eg. the faith of a Jewish believer can be easily damaged if we were to chew on a pork spare rib in front of them. Illicit sex may be a bodily function, but in reality it involves the whole person and so affects the whole person. A Platonic dualism, where the physical and spiritual are independent and where the physical is a lower order of little concern, does not align with the Biblical view of a person as an integrated being of both body and soul. The body is even raised and transformed on the day of Christ's return. The sense is improved with an introduction; "you also say", CEV.
      th/ koilia/ "for the stomach" - digestive system. "Food is for digestion."
      th porneia/ (a) "sexual immorality" - fornication. The context implies "consorting with prostitutes." The RSV "immorality" is not specific enough.
      tw/ kuriw/ (oV) dat. "for the Lord" - The dative is either taking an instrumental sense", "you should use your body to serve the Lord", TH; or a local sense, "the body belongs to the Lord as the Lord belongs to the body", Barrett. "Belong" is best, although probably more in the sense of "incorporated with", "part of" and therefore "belonging to."

v14
      hgeiren (egeirw) aor. "raised" - raised up. Christ is raised, not rises; he is the object or the act.
      exegerei, exhgeiren, exegeirei (exegeirw) fut. "he will raise" - [and also] he will raise up [us through the power of him]. As well as future, there are past and present variants. The past tense, being the less probable reading and therefore possibly original, actually helps make Paul's argument, namely, that it would be quite unnatural for a person who has been raised with Christ and empowered to live for him (in a spiritual sense), to then go and visit prostitutes; "and he raised us also by his power", cf. NJB margin.

v15
      melh (oV) "members" - body parts. Since we are raised with Christ, we are one with Christ. Our very being is united to Christ. "Your bodies are parts of the body of Christ", CEV; "limbs and organs", REB.
      araV (airw) aor. part. "take" - having taken away, carried off, snatched, wrenched. The participle is adverbial, possibly consecutive, "since, therefore, I have taken the members of Christ shall I make them members of a prostitute?"
      poihsw (poiew) aor. subj. / fut. "shall I .... unite" - should/shall I make. Deliberative subjunctive, or a plain future indicative. Am I then going to / shall I "take the limbs which rightly belong to Christ and make them limbs which belong to a prostitute?", Barclay.
      mh genoito aor. mid. opt. "Never!" - may it not happen. Optative expressing a wish; "perish the thought", "God forbid", AV.

v16
      h "-" - or. Variant, probably not original.
      ouk oidate (oida) perf. "do you not know?" - Rhetorical question with the sense "aren't you aware?"; "Don't you realize that when a man joins himself to a prostitute he makes with her a physical unity?", Phillips.
      oJ kollwmenoV (kollaw) pres. pas. part. "he who unites himself" - the one joining himself. Participle as a substantive. Obviously intended, "has sexual relations with", TH.
      eJn swma estin "is one with her in body" - one body is. "Becomes physically one with her", REB, Barclay ..., although "physical" is probably going beyond what Paul means. The term "one body" reflects Genesis 2:24, "one flesh". The union he is referring to is surely psychosomatic. Sexual union "is an act which, by reason of its very nature, engages and expresses the whole personality in such a way as to constitute a unique mode of self-disclosure and self-commitment", D.S. Bailey.

v17
      eJn pneuma (a atoV) "one with him in spirit" - one spirit. "Paul is probably referring to the work of the Spirit, whereby through the one Spirit the believer's `spirit' has been joined indissolubly with Christ", Fee.

v18
      feugete (feugw) imp. "flee from" - run away from. "Flee" can be expressed in the terms of "avoid / keep away from"; "avoid sexual looseness like the plague", Phillips.
      thn porneian (a) "sexual immorality" - As noted above, the word primarily concerns dealings with prostitutes, so Phillips' "sexual looseness" is highly misleading. Barclay's specific "fornication" is more to the point, thus removing this verse from the arsenal of those who include, for example masturbation, etc. under the catch-all of "sexual immorality."
      "other" - Not found in the Greek text. Added for meaning and found in most translations. There is a good possibility that we have here the beginning of a new paragraph and that Paul is putting up another Corinthian slogan to demolish; "every sin that a person commits is outside the body", NRSV. If a quote, inverted comers need to be added. The slogan would imply that sin does not affect the self ("body"). Paul would argue that all sin affects the self, and when it comes to visiting prostitutes, any fool can see that it affects the self.
      anqrwpoV (oV) "a man" - In the sense of "human"; "all other sins that people may commit", NJB.
      ektoV tou swmatoV "outside his body" - outside the self. Of course, taken as a slogan, it is not true, although it is usually argued that it is true, ie. sexual sins are more serious than other sins, see below.
      eiV "against" - to, into, for. Fornication turns back on and "into" the self, "attacks / invades." This sin leaves the psychological imprint of the prostitute, which in turn, tares the self away from the Lord. The two unions are mutually exclusive. Paul is probably not arguing that fornication, unlike all other sin, damages the self, rather that it can be easily argued (if not demonstrated) that fornication damages the self, as does all sin. Paul is not implying that fornication is a greater sin than say the exploitation of the poor through wealth or power. It is interesting to note how this verse has helped influence the view that sexual sin is more serious than other sins, which view is reinforced in modern translations by the addition of "other", eg., "it is not possible to mention anything worse than fornication", Chrysostom.

v19
      Punctuation. The verse is probably a single sentence, " ....... and that you are not your own?", NAB.
      naoV (oV) "a temple" - a sanctuary. Commonly understood as the dwelling place of God; "the sanctuary of the Holy Spirit", Bruce. Note that Paul later develops the idea of the Holy Spirit resident in "the body of Christ", ie. the church. Here the body is the individual self of a believer, and that self is a sanctuary, a set-apart place to commune with the divine.
      en "who is in [you]" - in, with, by. This preposition can be read numerous ways: "within you", NRSV; "in you", TEV; "where the Holy Spirit lives", CEV; "your body is a temple of the indwelling Holy Spirit", REB. Best understood in the sense of "in union with", reflecting a relational idea rather than an actual indwelling (a continuation of the "one flesh" idea, of which sex is a visible expression of the "cleaving" in marriage.)