Speak to the people of Israel, saying: When anyone sins unintentionally in any of the Lord's commandments about things not to be done, and does any one of them: If it is the anointed priest who sins, thus bringing guilt on the people, he shall offer for the sin that he has committed a bull of the herd without blemish as a sin offering to the Lord. (NRSV 4:2-3)
Speak unto the children of Israel, saying, If a soul shall sin through ignorance against any of the commandments of the Lord concerning things which ought not to be done, and shall do against any of them: If the priest that is anointed do sin according to the sin of the people; then let him bring for his sin, which he hath sinned, a young bullock without blemish unto the Lord for a sin offering. (KJV 4:2-3)
When any of you sin in that you have heard a public adjuration to testify and—though able to testify as one who has seen or learned of the matter—do not speak up, you are subject to punishment. (NRSV 5:1)
And if a soul sin, and hear the voice of swearing, and is a witness, whether he hath seen or known of it; if he do not utter it, then he shall bear his iniquity. (KJV 5:1)
Stop snitching may be the law of the streets, but it is not a law in Leviticus. A witness to a crime who fails to testify is guilty of a sin before God. That said, there's no criminal penalty for committing this sin, which makes God look like a pushover compared to McGruff the Crime Dog.
Now Aaron's sons, Nadab and Abihu, each took his censer, put fire in it, and laid incense on it; and they offered unholy fire before the Lord, such as he had not commanded them. And fire came out from the presence of the Lord and consumed them, and they died before the Lord. (NRSV 10:1-2)
And Nadab and Abihu, the sons of Aaron, took either of them his censer, and put fire therein, and put incense thereon, and offered strange fire before the Lord, which he commanded them not. And there went out fire from the Lord, and devoured them, and they died before the Lord. (KJV 10:1-2)
Being careless when handling fire can be dangerous, as illustrated in this classic MTV reenactment of Nadab's and Abihu's fatal carelessness.
If she is cleansed of her discharge, she shall count seven days, and after that she shall be clean. On the eighth day she shall take two turtledoves or two pigeons and bring them to the priest at the entrance of the tent of meeting. The priest shall offer one for a sin offering and the other for a burnt offering; and the priest shall make atonement on her behalf before the Lord for her unclean discharge. (NRSV 15:28-30)
But if she be cleansed of her issue, then she shall number to herself seven days, and after that she shall be clean. And on the eighth day she shall take unto her two turtles, or two young pigeons, and bring them unto the priest, to the door of the tabernacle of the congregation. And the priest shall offer the one for a sin offering, and the other for a burnt offering; and the priest shall make an atonement for her before the Lord for the issue of her uncleanness. (KJV 15:28-30)
After a woman has her period, she has to go to the Tabernacle to make a couple of offerings for purification. One of these is a sin offering, because, um, having your period is a sin? In a manner of speaking, yes. For the Israelites, the flow of blood from a woman's body is not normal since blood belongs inside. The outflow of blood in menstruation is not a moral sin, but like an immoral act, it's inconsistent with the way things are supposed to be. A sin offering counteracts this, while a burnt offering covers the loss of blood as a loss of the woman's essence of life.
TLDR version: ancient law is weird.
Thus he shall make atonement for the Tabernacle, because of the uncleannesses of the people of Israel, and because of their transgressions, all their sins; and so he shall do for the tent of meeting, which remains with them in the midst of their uncleannesses. (NRSV 16:16)
And he shall make an atonement for the holy place, because of the uncleanness of the children of Israel, and because of their transgressions in all their sins: and so shall he do for the tabernacle of the congregation, that remaineth among them in the midst of their uncleanness. (KJV 16:16)
Every year on Yom Kippur, the Day of Atonement, the high priest atones for all of Israel's uncleanness and sins. It used to be an occasion for a huge party, until that ended with the notorious Karaoke Incident of 453 B.C.E.
You shall not go around as a slanderer among your people, and you shall not profit by the blood of your neighbor: I am the Lord. You shall not hate in your heart anyone of your kin; you shall reprove your neighbor, or you will incur guilt yourself. (NRSV 19:16-17)
Thou shalt not go up and down as a talebearer among thy people: neither shalt thou stand against the blood of thy neighbour: I am the Lord. Thou shalt not hate thy brother in thine heart: thou shalt in any wise rebuke thy neighbour, and not suffer sin upon him. (KJV 19:16-17)
In the book of Numbers, badmouthing someone is a way to get a nasty skin disease (see: our analysis). Scolding your neighbor, however, is an invitation for a good slap.
Say further to the people of Israel: Any of the people of Israel, or of the aliens who reside in Israel, who give any of their offspring to Molech shall be put to death; the people of the land shall stone them to death. (NRSV 20:2)
Again, thou shalt say to the children of Israel, Whosoever he be of the children of Israel, or of the strangers that sojourn in Israel, that giveth any of his seed unto Molech; he shall surely be put to death: the people of the land shall stone him with stones. (KJV 20:2)
Why is Israel's God so cheesed off by Molech in particular? Because of an offensive mash-up of human sacrifice to Molech with the worship of God. The seriousness of the crime is evident in God's command to stone the offender with stones, a far more painful punishment than stoning him with puppies.
If a man lies with his uncle's wife, he has uncovered his uncle's nakedness; they shall be subject to punishment; they shall die childless. If a man takes his brother's wife, it is impurity; he has uncovered his brother's nakedness; they shall be childless. (NRSV 20:20-21)
And if a man shall lie with his uncle's wife, he hath uncovered his uncle's nakedness: they shall bear their sin; they shall die childless. And if a man shall take his brother's wife, it is an unclean thing: he hath uncovered his brother's nakedness; they shall be childless. (KJV 20:20-21)
Since adultery is punishable by death, it appears that this law applies to having sex with your uncle's or brother's widow. God says that the punishment for this sin is childlessness. That's a pretty big deal in Israelite culture; why might it seem like a penalty fitting the crime?
And speak to the people of Israel, saying: Anyone who curses God shall bear the sin. One who blasphemes the name of the Lord shall be put to death; the whole congregation shall stone the blasphemer. Aliens as well as citizens, when they blaspheme the Name, shall be put to death. (NRSV 24:15-16)
And thou shalt speak unto the children of Israel, saying, Whosoever curseth his God shall bear his sin. And he that blasphemeth the name of the Lord, he shall surely be put to death, and all the congregation shall certainly stone him: as well the stranger, as he that is born in the land, when he blasphemeth the name of the Lord, shall be put to death. (KJV 24:15-16)
In Israel, the name of God is the common bond that unites the people as a nation. Leviticus treats disrespecting God's name much in the same way that the U.S. Constitution treats treason, except in the Bible, the offender will actually get rocks pitched at his head.
If you spurn my statutes, and abhor my ordinances, so that you will not observe all my commandments, and you break my covenant, I in turn will do this to you: I will bring terror on you; consumption and fever that waste the eyes and cause life to pine away. You shall sow your seed in vain, for your enemies shall eat it. (NRSV 26:15-16)
And if ye shall despise my statutes, or if your soul abhor my judgments, so that ye will not do all my commandments, but that ye break my covenant: I also will do this unto you; I will even appoint over you terror, consumption, and the burning ague, that shall consume the eyes, and cause sorrow of heart: and ye shall sow your seed in vain, for your enemies shall eat it. (KJV 26:15-16)
The overarching theme of Leviticus is God's contract with his people, so it's only natural that the worst punishments can be found in the covenantal judgments at the end of the book. Obeying God results in life and abundance. Disobedience—death, decay, and the consumption of Israel's God-blessed super seeds by hostile Angry Birds.