Numbers 19:14-16
19:14 “‘This is the law: When a man dies in a tent, anyone who comes into the tent and all who are in the tent will be ceremonially unclean seven days.
19:15 And every open container that has no covering fastened on it is unclean.
19:16 And whoever touches the body of someone killed with a sword in the open fields, or the body of someone who died of natural causes, or a human bone, or a grave, will be unclean seven days.
Numbers 19:22
19:22 And whatever the unclean person touches will be unclean, and the person who touches it will be unclean until evening.’”