Numbers 19:17-20

¹⁷And they shall take for the unclean person some of the ashes of the burnt purification-offering, and they shall put thereupon running water 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 have been there, and upon him that hath touched the bone, or the one 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 when he hath purified him on the seventh day, then shall he wash his clothes, and bathe himself in water, and shall be clean at evening.

²⁰But a man that is unclean, and doth not purify himself, that soul shall be cut off from among the congregation; because the sanctuary of the Lord hath he defiled; the water of sprinkling hath not been sprinkled upon him; he is unclean.