Already in the early 2nd millennium B.C.E., people knew that diseases were contagious, and fear of contagion plays a key role in the Torah’s laws regarding the skin ailment, tzaraʿat. What does this mean for understanding other kinds of tum’ah?

Leviticus 15 describes two types of impure bleeding for women: menstruation (niddah), and bleeding that is “not during her menstrual period (zavah).” The Rabbis attempt to define the difference in an abstract manner, and in so doing, elide the two.

According to Leviticus 15:24, sex with a menstruating woman results in temporary impurity but seems to be allowed. According to Leviticus 18:19 and 20:18, on the other hand, it is strictly prohibited. What accounts for these two different approaches?

In Leviticus 15, the laws of niddah are about purity; Lev 18 and 20, however, prohibit sex during menstruation. The rabbis, who inherited both of these texts, create a new, hybrid concept: the prohibition of sex while a woman has the status of menstrual impurity.

A rejoinder to Rabbi Dr. Zev Farber’s “The Purification of a Niddah: The Torah Requirement.”

Despite its lengthy coverage of tzaraat, biblical “leprosy,” the Torah omits discussion of its cause, its infectiousness, and its treatment. Comparison to the Mesopotamian rituals pertaining to a strikingly similar disease, Saḫaršubbû, shows that these omissions were far from accidental.

The Archaeological and Textual Evidence 

When and why washing became immersion: between traditional-rabbinic and scientific-critical approaches to the origin of immersion and the mikveh.

Jewish law requires a menstruant woman to purify herself by immersing in water. A schematic look at Leviticus 15 actually implies this is not a Torah requirement.

Immersing in the Priestly Text