I was asked the following question by a Facebook friend: “How do you argue against gay marriage when pro-gay marriage activists say that gay [sic] marriage is forbidden in the Old Testament, but so is [eating] shellfish. They try to say that along with gay marriage that other stuff like shellfish is also forbidden. How do we as Christians respond?

Arguments like the “shellfish game” fill the internet, and many people are duped by them. Even Christians. In an interview published in Christianity Today magazine, Christian music artist and self-avowed lesbian Jennifer Knapp used the shellfish argument. (The interviewer did not challenge her on it.) There are several ways to argue against this false analogy. First, sexual relationships are defined in the earliest chapters of Genesis. Adam’s solitude was remedied with the creation of Eve, a female, someone designed specifically for him (Gen. 2:18–25). God didn’t create another man and also a woman so Adam could choose. He created a woman, a human complement designed sexually literally to fit with Adam. This is why Paul described homosexuality as “unnatural” (Rom. 1:26–27). The physical side of homosexual is unnatural, like trying to pound a square peg into a round hole. The shellfish argument has no validity since sexual identity (male and female) and the definition of marriage (man and woman) are creation ordinances. There is no prohibition in Genesis regarding shellfish (Gen. 1:28–31).

Second, the New Testament follows the Old Testament creation ordinance of marriage defining it as between a man and a woman. Jesus confirms this in Matthew 19:4–6: “Have you not read that He who created them from the beginning made them male and female, and said, ‘For this reason a man shall leave his father and mother and be joined to his wife, and the two shall become one flesh’? ‘So they are no longer two, but one flesh. What therefore God has joined together, let no man separate’” (also see Eph. 5:25–33; cf. 1 Cor. 7:2–3, 10–16; 1 Tim. 3:2, 12). There is no homosexual option. Jesus does not go to Leviticus to make His case; He goes back to Genesis.

Third, Leviticus, in addition to prohibiting homosexual relationships (Lev. 18:22; 20:13), also prohibits eating certain foods (Lev. 11:2–31). Unlike homosexuality, there are no civil penalties attached to eating from the prohibited food list. It’s obvious, in terms of the sanctions, that eating shellfish is not the same as engaging in homosexual relationships. With the coming of Jesus, the Second Adam, we are back to the creation ordinances where all foods are once again “clean” because the gospel is for the world (John 4:42; Acts 1:8):

And He said to them, “Are you also as lacking in understanding? Don’t you realize that nothing going into a man from the outside can defile him? For it doesn’t go into his heart but into the stomach and is eliminated.” (As a result, He made all foods clean.) Then He said, “What comes out of a person—that defiles him. For from within, out of people’s hearts, come evil thoughts, sexual immoralities, thefts, murders, adulteries, greed, evil actions, deceit, promiscuity, stinginess, blasphemy, pride, and foolishness. All these evil things come from within and defile a person.” (Mark 7:18–23)

Other passages address the same issue (Rom. 14:2-3, 6, 14-23 and Col. 2:16-23). Why are once prohibited foods now considered “clean”? We learn from Peter’s encounter with the “unclean foods” that he was told by God to eat that they represented the nations (Acts 10:9–48; 11:5–9): “What God has cleansed, no longer consider unholy” (10:15; 11:9). To eat foods that were set aside as unclean is an acknowledgment that the gospel is not just for Jews: “‘Therefore if God gave to them [Gentiles] the same gift as He gave to us [Jews] also after believing in the Lord Jesus Christ, who was I that I could stand in God’s way?’ When they heard this, they quieted down and glorified God, saying, ‘Well then, God has granted to the Gentiles also the repentance that leads to life’” (11:17–18).

Fourth, from Jesus’ comments in Mark 7 and God’s instructions to Peter in Acts 10, there is direct special revelation given that changes a number of laws from the Old Testament. In addition to unclean foods, there is no longer any use for the temple, animal sacrifices, and circumcision. How do we know this? Because we are told that these ordinances and laws no longer apply or are fulfilled in the person and work of Jesus Christ. We’re even told that there needed to be a change in the law, but in this case only as regarding who can be a priest (Heb. 7). Anyone familiar with the Bible knows these things.

Fifth, like the laws prohibiting homosexuality found in Leviticus, the New Testament prohibits homosexuality (Rom. 1:26–27; 1 Cor. 6:9–11; 1 Tim. 1:8–11), and if it prohibits homosexuality, then it prohibits homosexual marriage. Notice what Paul says in 1 Corinthians 6:9: “And such were some of you.” Some might claim that the Bible does not use the word “homosexual.” The definition is inherent in the Leviticus passages (18:22; 20:13): “You shall not lie with a male as one lies with a female.” That is, it is forbidden to engage in sexual relations with someone of the same (Latin: homo) sex. Paul uses similar language: “woman . . . burned in their desire toward one another, men with men [same sex with same sex]. . .” (Rom. 1:26–27).

Sixth, the same “Holiness Code” that condemns homosexuality also prohibits adultery (Lev. 18:20), child sacrifice (v. 21), and sex with animals (v. 23) and promotes loving your neighbor as yourself (19:18), a law repeated numerous times in the New Testament (Matt 19:19; Mark 12:31; Luke 10:27; Rom 13:9; Gal 5:14; James 2:8). Are the “shellfishers” telling us that adultery, child sacrifice, and sex with animals are now acceptable alternative lifestyle choices that should be protected by law? If his answer is yes, then let them say so. The New Testament promotes the Holiness Code law regarding loving one’s neighbor as well as laws prohibiting homosexual activity (Rom. 1:26–27; 1 Cor. 6:9–10; 1 Tim. 1:8–11). It seems that the New Testament writers do not have problems applying the Holiness Code legislation in the New Covenant.

Leviticus 19 (still part of the Holiness Code)—between the anti-homosexual passages of Leviticus 18:22 and 20:13—prohibits stealing and lying (v. 11), oppressing neighbors and robbing them (v. 13), withholding wages from a laborer (v. 13), cursing the deaf and tripping the blind (v. 14), showing partiality in judicial matters (v. 15), slandering (v. 16), and taking vengeance (v. 18). Leviticus 20 repeats prohibitions against child sacrifice (vv. 2–5), adultery (v. 10), homosexuality (v. 13), and bestiality (vv. 15–16). Are we to conclude, using shellfish logic, that these laws no longer apply today because they are found in the Holiness Code?

Some Christians will argue against the “shellfishers” on the basis that under the New Covenant we are not “signatories to the Sinaitic Covenant.” On the surface, this might seem like a good approach to take, but in practice it breaks down since the New Testament writers appeal to laws found in the covenant given at Sinai. Jesus quotes Leviticus 19:18 (Matt. 19:19; Mark 12:31; Luke 10:27) and 20:9 (Mark 7:10).  Paul also quotes Leviticus 19:18 (Rom 13:9; Gal 5:14), as does James (James 2:8). Paul took the Old Testament law seriously enough to apply a law that seemingly was only applicable to animals (Deut. 25:4) and applied its principles twice to humans (1 Cor. 9:9; 1 Tim. 5:18). If Paul could find contemporary application of a law that applied to oxen, then certainly the rest of the legal corpus has similar applicational force, even if we might not always know how to apply it.