'Purify Yourselves' in the Bible

And encamp ye without the camp seven days: whosoever hath killed any person, and whosoever hath touched any slain, purify yourselves on the third day and on the seventh day, ye and your captives.

And as to every garment, and all that is made of skin, and all work of goats hair , and all things made of wood, ye shall purify yourselves.