Ezekiel 39:12
The house of Israel will be burying them for seven months in order to purify the land.
Deuteronomy 21:23
his body must not remain overnight on the tree. You must bury him that same day, because cursed of God is the one who has been hanged on a tree. Don't defile your land that the LORD is about to give you as your inheritance."
Ezekiel 39:14
"Men will be assigned to travel continuously throughout the land, exploring for seven full months as they go about burying the bodies that remain from the battle on the surface of the ground, so that the land may be sterilized.
Ezekiel 39:16
They'll also name the city that is there "Hamonah,' as they purify the land."
Numbers 19:16
Whoever is out in an open field and touches the body of someone who was killed by a sword, or a dead body, or someone's bones, or a grave, he is to be considered unclean for seven days.