'Purification' in the Bible

So you will do to them, to purify them: sprinkle on them waters of purification, and {they will shave their whole body} and wash their garments.

A clean man will gather the ashes of the heifer, and he will put [them] in a clean {place outside the camp}; it will be for the community of the {Israelites} as a requirement for waters of impurity; it [is] a purification [offering].

For the unclean [person] they will take from the powder of the {burnt purification offering}, and they will put running water into a container.

And they brought seven bulls, seven rams, seven lambs, and seven male goats as a purification offering for the kingdom, for the sanctuary, and for Judah. And he commanded the descendants of Aaron, the priests, to offer [them] on the altar of Yahweh.