A bodily discharge (15:2). The male impurity stems from an abnormal urethral discharge that could consist of pus or excessive mucus and which could be caused by gonorrhea.132 As an alternative, J. V. Kinnier-Wilson has suggested that it could be caused by infectious urinary bilharzia, an ailment known to have been a problem in antiquity, which was produced by the parasite schistosoma, related to snails in water systems that have been detected by archaeologists.133 The abnormal female condition in Leviticus 15 has to do with a chronic vaginal discharge of blood, which arises from a disorder of the uterus.134
Whoever touches any of the things that were under him will be unclean (15:10). A discharge from the genitals directly contaminated objects underneath, such as a bed or chair, which would secondarily contaminate anyone else who touched them. A Mesopotamian incantation also speaks of secondary contamination by sleeping on the bed, sitting in the chair, eating at the table, or drinking from the cup of an accursed person.135 In this and other Mesopotamian texts, the contagion is demonic: “The common notion in these contexts was that the sinner, or defiled, or diseased individual was liable to demonic attack, and it is the demons themselves who are the contagious agents.”136 For Israelites, such terrible fear was gone and no exorcism was necessary.
When a man has an emission of semen (15:16). A Mesopotamian omen says: “If a man ejaculates in his dream and is spattered with his semen—that man will find riches; he will have financial gain.”137 But in the Israelite religious system, any seminal discharge, including nocturnal emission (Deut. 23:11), generated ritual impurity. Nevertheless, this impurity simply disqualified a person from coming in contact with holy things. There was no acknowledgment of the belief held by some ancient people (such as Hittites) that nocturnal emissions indicated sexual relations with spirits, even with deceased family members.138
An Israelite who engaged in sexual relations was barred from entering the sacred precincts of the sanctuary until evening. The situation was similar for Egyptians, but differed in other religious cultures, where ritualized sex flourished. The Hittite “Instructions to Priests and Temple Officials” prohibit cultic functionaries from defiling sancta (on pain of death for a kind of intentional violation; cf. Lev. 22:9) by approaching sacrificial loaves and libation vessels without bathing after sexual intercourse. But that is all. There is no waiting period and no prohibition of sexual activity elsewhere in the temple precincts.139 So all in all, the Israelite system put greater emphasis on the difference between the holy, immortal deity and mortal human beings, whose creative/reproductive functions only generate more human beings subject to death.