In Parashat Acharei Mot, we read: "You must keep My laws and My rules, you must not do any of those abhorrent things, neither the citizen nor the stranger who resides among you; for all those abhorrent things were done by the people who were in the land before and the land became defiled. So let not the land vomit you out for defiling it, as it spewed out the nation that came before you." (Lev. 18:26-28). ... In Torah, we see rain as relationship, an earth woven with ethic. Blessing is felt through pastoral plentitude, punishment through agricultural atrophy.
For the life of all flesh — its blood is its life. Therefore I say to the Israelite people: You shall not partake of the blood of any flesh, for the life of all flesh is its blood. Anyone who partakes of it shall be cut off. (Leviticus 17:14)
The Book of Leviticus could be nicknamed "The Journal of Blood and Water." Throughout its chapters we find the words tamei — translated as "impure," and tahor — translated as "pure" — as markers of a system of taboos so strong, the penalty for daring to dismiss them is kareit, or "excommunication." The taboos for certain sexual practices are painstakingly outlined in chapter 18, the section of Acharei Mot that we read on this Shabbat.