'Purify' in the Bible

And in the eighteenth year of his reign, to purify the land and the house he hath sent Shaphan son of Azaliah, and Maaseiah head of the city, and Joah son of Johaz the remembrancer, to strengthen the house of Jehovah his God.

Beth. With what doth a young man purify his path? To observe -- according to Thy word.

Seven days they purify the altar, and have cleansed it, and filled their hand.

Purify themselves, yea, make themselves white, yea, refined are many: and the wicked have done wickedly, and none of the wicked understand, and those acting wisely do understand;