במדבר י״ט:כ׳

GOD spoke to Moses and Aaron, saying: This is the ritual law that GOD has commanded:
Instruct the Israelite people to bring you a red cow without blemish, in which there is no defect and on which no yoke has been laid. You shall give it to Eleazar the priest. It shall be taken outside the camp and slaughtered in his presence. Eleazar the priest shall take some of its blood with his finger and sprinkle it seven times toward the front of the Tent of Meeting. The cow shall be burned in his sight—its hide, flesh, and blood shall be burned, its dung included— and the priest shall take cedar wood, hyssop, and crimson stuff, and throw them into the fire consuming the cow. The priest shall wash his garments and bathe in water; after that the priest may reenter the camp, but he shall be impure until evening. The one who performed the burning shall also wash their garments in water, bathe, and be impure until evening. Someone else who is pure shall gather up the ashes of the cow and deposit them outside the camp in a pure place, to be kept for water of lustration^awater of lustration Lit. “water for impurity.” for the Israelite community. It is for purgation. The one who gathers up the ashes of the cow shall also wash their clothes and be impure until evening.
This shall be a permanent law for the Israelites and for the strangers who reside among them. Anyone who touches the corpse of any human being shall be impure for seven days. They shall undergo cleansing with [the ashes] on the third day and on the seventh day, and then be pure; if they fail to undergo cleansing on the third and seventh days, they shall not be pure. Whoever touches a corpse—the body of a person who has died—and does not undergo cleansing, defiles GOD’s Tabernacle; that person shall be cut off from Israel. Since the water of lustration was not dashed on them, they remain impure; their impurity is still upon them. This is the ritual: When a person dies in a tent, whoever enters the tent and whoever is in the tent shall be impure seven days; and every open vessel, with no lid fastened down, shall be impure. And in the open, anyone who touches a person who was killed^bkilled Lit. “slain by the sword.” or who died naturally, or human bone, or a grave, shall be impure seven days. Some of the ashes^cashes Lit. “earth” or “dust.” from the fire of purgation shall be taken for the impure person, and fresh water shall be added to them in a vessel. Then someone who is pure shall take hyssop, dip it in the water, and sprinkle on the tent and on all the vessels and people who were there, or on the one who touched the bones or the person who was killed or died naturally or the grave. The pure person shall sprinkle it upon the impure person on the third day and on the seventh day, thus cleansing that person by the seventh day. [The latter] shall then wash their clothes and bathe in water—and at nightfall shall be pure. If anyone who has become impure fails to undergo cleansing, that person shall be cut off from the congregation for having defiled GOD’s sanctuary. The water of lustration was not dashed on them—they are impure. That shall be for them a law for all time. Further, whoever sprinkled the water of lustration shall wash their clothes; and whoever touches the water of lustration shall be impure until evening. Whatever that impure person touches shall be impure; and the person who touches [that impure one] shall be impure until evening.