Chapters 18-20 of Leviticus give moral instruction to the Israelites that separate them from the surrounding cultures. Chapter 18 deals primarily with the institution of marriage and sets strict boundaries around sexual intercourse. Chapter 19 gives positive instruction to the people about how to treat each other in their everyday lives. Chapter 20 spells out the maximum punishments that were to be given for the most serious offenses (mostly from chapter 18).
Beginning in chapter 18, verses 1-6, we read the overall purpose for the following chapters. The Israelites are prohibited from following the practices of the Egyptians (from where they came) and the Canaanites (where they are going).
Why? Because “I am the LORD your God.” Three times God reminds them in these verses that He is the “LORD your God.” In fact, in chapters 18-20, the phrase “I am the LORD your God,” or something close to it, is repeated almost 50 times! This phrase would communicate at least three things to the Israelites, according to Gordon Wenham.
First, “it looks back to the redemption of Israel from slavery in Egypt.” It is a reminder that he brought them out of Egypt.
Second, “Israel, as the people of God, was expected to imitate God, to be holy. ‘For I am the Lord your God, and you must sanctify yourselves and be holy, because I am holy’ (Lev. 11:44).”
Third, “this phrase often provides the motive for observing a particular law. Under the covenant the people of God were expected to keep the law, not merely as a formal duty but as a loving response to God’s grace in redemption.”
Verse 6 states the main thrust of chapter 18, to prohibit marriage, and therefore sexual intercourse, between close relatives. Verses 6-18 spell out the incest prohibitions in detail. Wenham explains the basic principles underlying the rules in verses 6–18: “a man may not marry any woman who is a close blood relation, or any woman who has become a close relative through a previous marriage to one of the man’s close blood relations. All the relationships prohibited here can be seen to be out-workings of these two basic principles.”
So why are so many verses dedicated to incest in chapter 18? Mark Rooker explains:
“But the issue of incest in Israel was more problematic than in other cultures. This was due to two separate but related factors. First, the Israelites were not allowed to intermarry with foreigners, particularly the Canaanites. This obviously greatly reduced the number of possible marriage candidates. Second, the lands that a family or clan inherited were to remain inside the family or clan, necessitating that marriages take place between relatives. These two restrictions made incest laws indispensable. Sexual energies had to be subordinated to God’s will.”
Verses 19-23 identify other pagan customs that were to be avoided by Israel. These included sex during menstruation, adultery, child prostitution/sacrifice, homosexual acts, and bestiality.
Verses 24-30 record the curses that will fall upon the nation if they follow the pagan practices outlined in the previous verses. God warns Israel that he will drive them out of the land, just as he is driving out the Canaanites for the sins they have committed. The picture given is that of the land literally vomiting out its inhabitants for their sins. Several hundred years later, the Israelites would indeed be exiled from Canaan for their sins.
In chapter 19, God tells the people how to treat each other in their daily lives. Chapter 19 repeats almost all of the Ten Commandments, expanding upon them. Remember that the Ten Commandments are the foundational moral principles for Israel, and that all of the laws and rules coming after the Commandments are details meant to help the Israelites apply them to their lives.
Verses 9-18 are illustrative of the kinds of behaviors God desires from his people. These actions are what will make the people of Israel holy, just as God is holy. God expects the Israelites to: 1) leave food for the poor who have no land, 2) not steal from each other, 3) not lie to each other, 4) not defraud or rob each other, 5) not hold back earned wages, 6) not take advantage of the disabled, 7) not show partiality in legal matters, 8) not slander each other, 9) not endanger each other’s lives, 10) confront each other about sins, 11) not seek revenge against each other.
The final culmination of all these instructions is in verse 18: “love your neighbor as yourself.” Mark Rooker writes:
“This statement, ‘love your neighbor as yourself,’ forms a climax to this first major section, and it was regarded by some as the central principle of the Law. The significance of the verse is also highlighted by the fact that Jesus and Paul both cited this verse as a summary of the duties one has to his fellow man (Matt 22:39–40, Rom 13:9).”
“Love your neighbor as yourself” is also repeated in several other New Testament passages, showing how important Lev 19:18 is to the New Testament writers: Matt 19:19; Mark 12:31; Luke 10:27; Gal 5:14; and Jas 2:8.
Finally, in chapter 20, God describes the punishments for the most serious sins listed in previous chapters. Keep in mind that God has already commanded the people to not commit these sins, so chapter 20 answers the question: “what do we do with people who commit these sins?”
Most, but not all, of the punishments in chapter 20 either call for the offender to be put to death by the community (stoning being the most prevalent method), or by God “cutting them off.” In the cases where God promised to “cut them off,” this was understood to be a death sentence to be executed by God himself. The community would not, in this case, execute the offender, but leave matters in God’s hands.
What kinds of sins deserved the death penalty? Those crimes that were committed against religion and against the family unit. God considers these sins to be the most serious. Verses 2-6 cover religious sins and verses 9-21 cover sins against the family.
In verses 1-5, we see the first religious offense deserving of the death penalty. “Any Israelite or any alien living in Israel who gives any of his children to Molech must be put to death. The people of the community are to stone him.” So what does giving children to Molech mean?
There are two practices from Israel’s neighbors that are likely prohibited here. First, some parents would dedicate their daughters, at birth, to become a temple prostitute for the god Molech. Second, some parents would offer their children to be sacrificed to Molech. Generally, the children would be killed, and then burned in the “arms” of a Molech statue.
In verse 3, God explains that his name is profaned when his people worship Molech by offering their children. To the outside world, God would be no different from any of the other false pagan gods worshipped in the ancient near east.
In verses 4-5, we see that God will also place a death sentence on any people who know that child sacrifice to Molech is occurring, but who don’t report it. Thus God makes the entire community responsible for rooting out this particular form of evil.
The remainder of chapter 20 lists many other sins that are punishable by death. By calling out these particular sins, God is clearly communicating how seriously he takes these offenses to be.