Ezekiel 39:14
39:14 They will designate men to scout continually through the land, burying those who remain on the surface of the ground, in order to cleanse it. They will search for seven full months.
Ezekiel 39:16
39:16 (A city by the name of Hamonah will also be there.) They will cleanse the land.’
Numbers 19:16
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.
Deuteronomy 21:23
21:23 his body must not remain all night on the tree; instead you must make certain you bury him that same day, for the one who is left exposed on a tree is cursed by God. You must not defile your land which the Lord your God is giving you as an inheritance.