Numbers 19:14-16

14This is the rule when a person dies in a tent. Any person who is in the tent will not be clean for seven days.

15Any pot in the tent that does not have a lid will not be clean.

16Also, a person might have killed someone with a sword out in the country. Or someone may have died because he was old or ill. Anyone who touches a dead body in the country will become unclean for seven days. Also if they touch a human bone, or a grave, that person will be unclean for seven days.