Red heifer

The Red Heifer (Hebrew: פָרָ֨ה אֲדֻמָּ֜ה‎‎; para adumma), also known as the red cow, was a cow brought to the priests as a sacrifice according to the Hebrew Bible, and its ashes were used for the ritual purification of Tum'at HaMet ("the impurity of the dead"), that is, an Israelite who had come into contact with a corpse.

According to Numbers 19:2: "Speak unto the children of Israel, that they bring thee a red without spot, wherein is no blemish, and upon which never came yoke".

The Book of Numbers stipulates that the cow must be red in color, without blemish, and it must not have been used to perform work (Numbers 19:2). The heifer is then ritually slaughtered (Numbers 19:3) and burned outside of the camp (Numbers 19:3–6). Cedar wood, hyssop, and wool or yarn dyed scarlet are added to the fire, and the remaining ashes are placed in a vessel containing pure water (Numbers 19:9).

In order to purify a person who has become ritually contaminated by contact with a corpse, water from the vessel is sprinkled on him, using a bunch of hyssop, on the third and seventh day of the purification process (Numbers 19:18–19).

The priest who performs the ritual then becomes ritually unclean, and must then wash himself and his clothes in running waters. He is deemed impure until evening.

The Mishnah, the central compilation of Rabbinic Oral Law, contains a tractate on the Red Heifer, Tractate Parah ("Cow") in Seder Tohorot, which explains the procedures involved. The tractate has no existing Gemara, although commentary on key elements of the procedure is found in the Gemarah for other tractates of the Talmud. According to Mishnah Parah, the presence of two black hairs invalidates a Red Heifer, in addition to the usual requirements of an unblemished animal for sacrifice.

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