'Redeemed' in the Bible

Now these are thy servants and thy people, whom thou hast redeemed by thy great power, and by thy strong hand.

And I said unto them, We after our ability have redeemed our brethren the Jews, which were sold unto the heathen; and will ye even sell your brethren? or shall they be sold unto us? Then held they their peace, and found nothing to answer.

These have sought their register among those reckoning themselves by genealogy, and it hath not been found, and they are redeemed from the priesthood,

Be mindful of them, O my God, for the redeemed of the priesthood, and the covenant of the priesthood, and of the Levites.