Numbers 19:11

9 Then a man who is ceremonially clean is to gather up the ashes of the heifer and store them in a ceremonially clean place outside the camp. They must be kept by the congregation of Israel for preparing the water of purification; this is for purification from sin.

10 The man who has gathered up the ashes of the heifer must also wash his clothes, and he will be ceremonially unclean until evening. This is a permanent statute for the Israelites and for the foreigner residing among them.

11 Whoever touches any dead body will be unclean for seven days.

12 He must purify himself with the water on the third day and on the seventh day; then he will be clean. But if he does not purify himself on the third and seventh days, he will not be clean.

13 Anyone who touches a human corpse and fails to purify himself defiles the tabernacle of the LORD. That person must be cut off from Israel. He remains unclean, because the water of purification has not been sprinkled on him, and his uncleanness is still on him.