Numbers 19:17-19

¹⁷And they shall take for the unclean of the ashes of the purification-offering that hath been burned, and shall put running water thereon in a vessel;

¹⁸and a clean man shall take hyssop, and dip it in the water, and sprinkle it on the tent, and upon all the utensils, and upon the persons that were there, and upon him that hath touched the bone, or the one slain, or the dead person, or the grave;

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