Numbers 19:7-10

7The priest 1shall then wash his clothes and bathe his 2body in water, and afterward come into the camp; but the priest will be 3unclean until evening. 8The one who burns 4the heifer shall also wash his clothes in water and bathe his 5body in water, and will be unclean until evening. 9Now a man who is clean shall gather up the ashes of the heifer and put them outside the camp in a clean place, and 6the congregation of the sons of Israel shall keep them for 7water to remove impurity; it is 8purification from sin. 10And the one who gathers the ashes of the heifer 9shall wash his clothes and will be unclean until evening; and it shall be a permanent statute for the sons of Israel and for the stranger who resides among them.