I am still in the introduction to Jacob Milgrom’s Leviticus.
Christians and other Gentiles may ignore Leviticus because everything there seems to apply only to Israel. But Milgrom puts the book in a more universal context. If you look at P’s stratum in Genesis, you find a story that includes the whole human race. God created a world of which he said “it is very good.” However, human violence soon clouded this world leading to the flood.
After the flood, in Genesis 9:4-6, God gave humanity a law to remedy the violence that P saw as a scourge upon the world. This was based on the priestly view that “human society is viable only if it desists from the shedding of human blood and animal blood.” So the P source “declares its fundamental premise that human beings can curb their violent nature through ritual means, specifically, a dietary discipline that will necessarily drive home the point that all life, shared also by animals, is inviolable , except–in the case of meat–when conceded by God.”
Furthermore Milgrom says, “the blood prohibition proves that P is of the opinion that a universal God imposed a basic ritual code upon humanity in general, Israel, nonetheless, –bound by its covenental relationship with the Diety–is enjoined to follow a stricter code of conduct.”
(All the above quotes are from the section of the introduction, “The Priestly Theology of Chapters 1-16: A Survey”. I am not able to find page numbers for this Kindle book.)
He gives us much insight into the priestly concept of purity. Much of the religion of people around Israel that comes out in the texts we have from Mesopotamia, for instance, was about dealing with the occult world of demons and malevolent spirits. Inhabiting spirits made contact with certain things dangerous or contaminating. But this was not the symbolic world of the priests. In their world what made one unclean or impure was not evil spirits.
The main players in the symbolic world of P were life and death. Contact with death contaminated you and made you ritually unclean. Skin disease, for instance, was not treated medically, as we would do, or magically, as Israel’s neighbors would do. Disease, itself was part of life and did not make you impure. But some skin diseases gave you the look of death (see Numbers 12:2). It was the association with death that had to do with purity.
The discharge of semen or menstrual blood made things that touched them impure. This is because semen and blood contain life force. Losing these symbolizes death. Men and women were not themselves impure because of a genital discharge. Contact with the semen or blood brought about the impurity.
Contact with actual death–corpses–caused impurity, as well.
The other side of this symbolic world was that Israel’s one God stood over against death, for life and holiness.
The impurity was not moral or ethical unless you failed to follow the commands for dealing with it. It mostly affected your ability to come into contact with holy things after being in contact with death. There were purifying rites to deal with this. So, if the word “purity” causes you to think of the Puritans or the contemporary purity movement where young people pledge to preserve their virginity until marriage, understand that Jewish purity is something else altogether.
So you could say the priests removed myth and animism from Israel’s symbolic system. This may have been something that evolved over time. In older stories there is sometimes a aura of fear and magic. But the priestly legislation removes most of this or reinterprets it.
The opposite of impurity is holiness. So the idea of ritual impurity in P is an essential background to the notion of ethical holiness stressed in what Milgrom sees as the reform movement represented in the last ten chapters of Leviticus.
But I see what Milgrom means when he says that even the ritual laws have ethical concern. You have to look at them from the standpoint of the priest’s concern with bloodshed and with life and death.