'Grave' in the Bible

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.

A clean person is to take some hyssop, dip it in water, and then sprinkle it on the tent, on every vessel, and on whoever was there (that is, on whoever touched the bones, the killed person, or the dead body, including whoever dug the grave).