Why does Leviticus 18 tell Israel to follow God’s commands rather than the customs of Egypt and Chanaan?

Atlas of Saints · Chapter summary

God says that the person who keeps his laws shall live in them. He forbids the listed sexual acts and consecration of offspring to Moloch, warning that these acts defile people and the land and can bring removal from the land and perishing from the people.

Chapter breakdown

Leviticus 18 sets out forbidden family relationships and sexual acts. The Lord tells Moses to speak to the children of Israel: he is the Lord their God. They must not follow the customs of Egypt, where they lived, or the ways and ordinances of Chanaan, where he will bring them. They must carry out his judgments, keep his commands, and walk in them. God says that the person who keeps his laws and judgments shall live in them.

No man may approach a woman who is near kin to uncover her nakedness, meaning sexual intimacy. The Lord forbids uncovering the nakedness of one’s father or mother, emphasizing that she is one’s mother. A man must not uncover the nakedness of his father’s wife, because it is his father’s nakedness. Nor may he uncover the nakedness of a sister by his father or his mother, whether she was born at home or abroad.

A man must not uncover the nakedness of his son’s daughter or his daughter’s daughter, because it is his own nakedness. The same ban applies to his father’s wife’s daughter whom she bore to his father, because she is his sister. It also applies to his father’s sister, because she is his father’s flesh, and to his mother’s sister, because she is his mother’s flesh.

A man must not uncover the nakedness of his father’s brother, nor approach that uncle’s wife, who is related to him by marriage. He must not uncover the nakedness of his daughter-in-law or expose her shame, because she is his son’s wife. He must not uncover the nakedness of his brother’s wife, because it is his brother’s nakedness.

A man must not uncover the nakedness of his wife and her daughter. He must not take her son’s daughter or her daughter’s daughter to expose her shame, because they are her flesh; the text calls such sexual relations incest. He must not take his wife’s sister as a prostitute to rival his wife or uncover the sister’s nakedness while his wife is living. The wife’s lifetime is an explicit condition of that last rule.

A man must not approach a woman during her menstrual period or uncover her nakedness. He must not lie with his neighbour’s wife or be defiled by the mingling of seed. He must not give any of his offspring to be consecrated to the idol Moloch or defile God’s name. The Lord also forbids a man to lie with a man as with a woman, calling it an abomination. A man must not have sexual relations with any beast or be defiled with it. A woman must not lie down to a beast or have sexual relations with it; the text calls this a heinous crime.

Challoner explains that the Hebrew expression translated as a heinous crime is the word “confusion,” signifying the shamefulness and baseness of this sin. This is a note about the wording of verse 23, rather than an added phrase in the verse.

The people must not defile themselves through any of these acts. God says that the nations he will cast out before them have defiled themselves and the land through them. He will punish the land’s abominations so that it vomits out its inhabitants. Both Israelites and strangers living among them must keep his ordinances and judgments and must not do any of these abominations. The previous inhabitants did these things and defiled the land. Israel must beware: if they do the same things, the land may vomit them out as it vomited out the nation before them.

Every person who commits any of these abominations shall perish from his people. God closes by telling them to keep his commands, not to do what those before them did, and not to be defiled by those acts. He is the Lord their God.

The story inside

The opening contrast is between customs learned in Egypt, customs awaiting Israel in Chanaan, and the commands of the Lord. God tells Israel to walk in his judgments and says that the person who does them shall live in them. The detailed family prohibitions make that instruction concrete: the chapter names parents, sisters, granddaughters, aunts, an uncle and his wife, and relatives through marriage rather than leaving the near-kin rule vague. It then lists other forbidden acts. The closing warning returns to the earlier inhabitants: their acts defiled the land, and Israel can face the same removal if it does the same things. The warning includes strangers living among Israel and gives a consequence for each person who commits the acts. The opening instruction and closing warning therefore give reasons for keeping the named commands.

Lessons worth keeping

1
God’s commands govern Israel’s conduct in both its former and future surroundings. The reason given is that the person who keeps his laws shall live in them; the text does not tell Israel simply to adopt local custom.
2
The family rules require attention to the named relationships. They include relatives by birth and marriage, and the wife’s-sister rule expressly includes the condition that the wife is still living. Replacing these details with a general label loses part of the law.
3
The warning applies to Israelites and strangers living among them. The previous inhabitants defiled the land through these acts, and Israel is warned that doing the same can bring the same removal; each offending person also faces perishing from his people.

Test your recall

Why does the chapter warn that the land may vomit Israel out, and how does that warning explain the command not to follow the former inhabitants’ acts?

The source heading at line 12600 prints “Anda all”; read “And all.” The original quotation is retained exactly.

Source edition and notes

Douay–Rheims, revised by Richard Challoner (1749–1752). Project Gutenberg no. 1581. Locators refer to lines in the admitted pg1581.txt edition. Source notes may include Challoner commentary.

Lines 12598–12617
Leviticus Chapter 18 Marriage is prohibited in certain degrees of kindred: Anda all unnatural lusts. 18:1. And the Lord spoke to Moses, saying: 18:2. Speak to the children of Israel, and thou shalt say to them: I am the Lord your God. 18:3. You shall not do according to the custom of the land of Egypt, in which you dwelt: neither shall you act according to the manner of the country of Chanaan, into which I will bring you. Nor shall you walk in their ordinances. 18:4. You shall do my judgments, and shall observe my precepts, and shall walk in them. I am the Lord your God. 18:5. Keep my laws and my judgments: which if a man do, he shall live in them, I am the Lord.
Lines 12619–12630
18:6. No man shall approach to her that is near of kin to him, to uncover her nakedness. I am the Lord. 18:7. Thou shalt not uncover the nakedness of thy father, or the nakedness of thy mother: she is thy mother, thou shalt not uncover her nakedness. 18:8. Thou shalt not uncover the nakedness of thy father’s wife: for it is the nakedness of thy father. 18:9. Thou shalt not uncover the nakedness of thy sister by father or by mother: whether born at home or abroad.
Lines 12632–12642
18:10. Thou shalt not uncover the nakedness of thy son’s daughter, or thy daughter’s daughter: because it is thy own nakedness. 18:11. Thou shalt not uncover the nakedness of thy father’s wife’s daughter, whom she bore to thy father: and who is thy sister. 18:12. Thou shalt not uncover the nakedness of thy father’s sister: because she is the flesh of thy father. 18:13. Thou shalt not uncover the nakedness of thy mother’s sister: because she is thy mother’s flesh.
Lines 12644–12652
18:14. Thou shalt not uncover the nakedness of thy father’s brother: neither shalt thou approach to his wife, who is joined to thee by affinity. 18:15. Thou shalt not uncover the nakedness of thy daughter in law: because she is thy son’s wife, neither shalt thou discover her shame. 18:16. Thou shalt not uncover the nakedness of thy brother’s wife: because it is the nakedness of thy brother.
Lines 12654–12661
18:17. Thou shalt not uncover the nakedness of thy wife and her daughter. Thou shalt not take her son’s daughter or her daughter’s daughter, to discover her shame: because they are her flesh, and such copulation is incest. 18:18. Thou shalt not take thy wife’s sister for a harlot, to rival her: neither shalt thou discover her nakedness, while she is yet living.
Lines 12663–12677
18:19. Thou shalt not approach to a woman having her flowers: neither shalt thou uncover her nakedness. 18:20. Thou shalt not lie with thy neighbour’s wife: nor be defiled with mingling of seed. 18:21. Thou shalt not give any of thy seed to be consecrated to the idol Moloch, nor defile the name of thy God. I am the Lord. 18:22. Thou shalt not lie with mankind as with womankind: because it is an abomination. 18:23. Thou shalt not copulate with any beast: neither shalt thou be defiled with it. A woman shall not lie down to a beast, nor copulate with it: because it is a heinous crime.
Lines 12679–12681
Because it is a heinous crime.... In Hebrew, this word heinous crime is expressed by the word confusion, signifying the shamefulness and baseness of this abominable sin.
Lines 12683–12697
18:24. Defile not yourselves with any of these things with which all the nations have been defiled, which I will cast out before you, 18:25. And with which the land is defiled: the abominations of which I will visit, that it may vomit out its inhabitants. 18:26. Keep ye my ordinances and my judgments: and do not any of these abominations. Neither any of your own nation, nor any stranger that sojourneth among you. 18:27. For all these detestable things the inhabitants of the land have done, that were before you, and have defiled it. 18:28. Beware then, lest in like manner, it vomit you also out, if you do the like things: as it vomited out the nation that was before you.
Lines 12699–12706
18:29. Every soul that shall commit any of these abominations, shall perish from the midst of his people. 18:30. Keep my commandments. Do not the things which they have done, that have been before you: and be not defiled therein. I am the Lord your God.