'Purify' in the Bible

Now the Passover of the Jews was at hand. Many went up from the country to Jerusalem before the Passover, to purify themselves.

Take them, and purify yourself with them, and pay their expenses for them, that they may shave their heads. Then all will know that there is no truth in the things that they have been informed about you, but that you yourself also walk keeping the law.

who gave himself for us, that he might redeem us from all iniquity, and purify for himself a people for his own possession, zealous for good works.

Draw near to God, and he will draw near to you. Cleanse your hands, you sinners; and purify your hearts, you double-minded.