“Every bed on which the zav lies shall be impure; and every vessel on which he sits shall be impure.”
I would like to introduce you to Zachary, the Zav. (A Zav is someone with poor personal hygiene who carries the essence of impurity with him.) Like many people in recent times, he has lost his job as a builder of earthenware ships and has hired himself out to a group of Rabbis who were looking for volunteers to test for immunities against contamination from impurity. Zachary decides to enter the gig economy, and although he is now making less than he did before, the extra income helps, and he believes he is providing a public service in the quest to find protection against impurity.
Zachary carries out a number of tasks for the Rabbis so that they can collect relevant data on impurity. They ask him to sit inside a wagon while they are busy taking measurements in order to determine how far the Zav’s impurity can travel. Is it three, six or twelve feet? They try to determine if the Zav can leave behind impurity on the surface of the wagon. They test the potential for contamination in both a wooden and stone wagon to determine if there are differences in the duration of the impurity and the surface that is invaded.
They next experiment with three types of chests and ask Zachary to sit upon each one. One chest opens from the side and they determine that it is a source of contamination because it can be opened while our resident Zav remains seated upon it. They bring forward a chest that opens from the top and decide that it is free from contamination because the source of impurity, our Zav, must stand up if it is opened. They drag out an enormous chest that they determine does not become impure even from the sitting Zav. The reason why remains a mystery and they note that this requires further investigation.
They ask Zachary to sit upon an earthenware vessel. He places his hands inside its mouth and the Rabbis note that the vessel becomes impure. They ask him to sit without moving or touching the vessel for fifteen minutes, which is the recorded amount of time that contamination can occur; it remains pure and they note that earthenware vessels hold up particulary well to impurities.
The Rabbis ask Zachary to recline on a bed that is made up for this purpose in their study hall, and determine that everything he touches becomes impure, including his clothes and sheets. Such contact is noted as high risk for contamination. They wash everything he has touched in steaming hot water to determine if it destroys the impurity, The Rabbis then drag out a cadaver and ask Zachary to touch its limbs in order to test for contamination. They want to determine if cross contamination can occur among two types of impurity.
Zachary does not have the stomach for this type of thing and decides that this particular gig might be more than he bargained for. He decides that he has had enough. He collects his pay and tells the Rabbis to find another Zav. His next gig is as a contact tracer. The hourly rate is higher than the Rabbis paid, and he believes he will provide an even greater service to society.