Prohibition of Kohen defilement by the dead

The prohibition of Kohen defilement to the dead is the commandment to a Jewish priest (kohen) not to come in direct contact with, or be in the same enclosed space as a dead body.

The command forbidding the priest from defilement by contact with a dead body is stated in the Book of Leviticus;

And the LORD said unto Moses, Speak unto the priests the sons of Aaron, and say unto them, There shall none be defiled for the dead among his people:

Although the priest, or modern kohen, is forbidden to come in contact with a dead body, he is permitted to become defiled for his closest relatives: father, mother, brother, unmarried sister, and child. Defilement of a Kohen to his wife, although implied in the Torah text as forbidden according to Maimonides and Even Ezra on Leviticus 21:3-4, is permitted by rabbinical order.

A Kohen is forbidden to enter any house or enclosure ("ohel", tent) in which a dead body (or part thereof), may be found (Leviticus 10:6, Leviticus 21:1–5, Ezekiel 44:20, Ezekiel 44:25). Practical examples of these prohibitions include: not entering a cemetery or attending a funeral; not being under the same roof (i.e. in a home or hospital) as a dismembered organ.

The rules and regulations of defilement are discussed at length in the Mishnah Tohorot. A cursory rule of thumb is that the kohen may not enter a room with a dead person.

Rabbinic prohibition further limits the Kohen of coming within four amoth of an outdoor (i.e. no roof or overhang present) corpse or grave, but a fence or groove with a height or depth of 10 tefachim eases the restriction and enables the Kohen to be within four tefachim of the corpse or grave.

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