'Purify' in the Bible
"Take the descendants of Levi from the Israelis and purify them.
This is what you must do to them for their purification: Sprinkle them with the purification water. Have them shave their entire bodies and wash their clothes, and so purify themselves.
And after this the Levites will come to serve [at] the tent of assembly, and you will purify them, and you {will offer} them [as] a wave offering.
The descendants of Levi therefore purified themselves, washed their clothes, and then Aaron presented them as wave offerings to the LORD. Aaron provided atonement for them to purify them.
“Tell the people: Purify yourselves in readiness for tomorrow, and you will eat meat because you cried before the Lord: ‘Who will feed us meat? We really had it good in Egypt.’ The Lord will give you meat and you will eat.
He shall purify himself with it on the third day, and on the seventh day he shall be clean: but if he purify not himself the third day, then the seventh day he shall not be clean.
Anyone who touches a body of a person who has died, and does not purify himself, defiles the tabernacle of the Lord. That person will be cut off from Israel. He remains unclean because the water for impurity has not been sprinkled on him, and his uncleanness is still on him.
And the clean person shall sprinkle upon the unclean on the third day, and on the seventh day: and on the seventh day he shall purify himself, and wash his clothes, and bathe himself in water, and shall be clean at even.
But the man that shall be unclean, and shall not purify himself, that soul shall be cut off from among the congregation, because he hath defiled the sanctuary of the LORD: the water of separation hath not been sprinkled upon him; he is unclean.
And do ye abide without the camp seven days: whosoever hath killed any person, and whosoever hath touched any slain, purify both yourselves and your captives on the third day, and on the seventh day.