Numbers 19:11, 16, 18

‘He who touches the dead body of anyone shall be unclean seven days.

Whoever in the open field touches one who is slain by a sword or who has died, or a bone of a man, or a grave, shall be unclean seven days.

A clean person shall take hyssop and dip it in the water, sprinkle it on the tent, on all the vessels, on the persons who were there, or on the one who touched a bone, the slain, the dead, or a grave.