Numbers 19:12-13
12
the same shall purify himself with water on the third day, and on the seventh day he shall be clean: but if he doesn't purify himself the third day, then the seventh day he shall not be clean.
13
Whoever touches a dead person, the body of a man who has died, and doesn't purify himself, defiles the tabernacle of Yahweh; and that soul shall be cut off from Israel: because the water for impurity was not sprinkled on him, he shall be unclean; his uncleanness is yet on him.