NUMBERS 19:17-20

¹⁷And for the unclean they shall take of the ashes of the burning of the sin offering, and running water shall be put thereto in a vessel:

¹⁸and a clean person shall take hyssop, and dip it in the water, and sprinkle it upon the tent, and upon all the vessels, and upon the persons that were there, and upon him that touched the bone, or the slain, or the dead, or the grave:

¹⁹and the clean person shall sprinkle upon the unclean on the third day, and on the seventh day: and on the seventh day he shall purify him; and he shall wash his clothes, and bathe himself in water, and shall be clean at even.

²⁰But the man that shall be unclean, and shall not purify himself, that soul shall be cut off from the midst of the assembly, because he hath defiled the sanctuary of the LORD: the water of separation hath not been sprinkled upon him; he is unclean.