Numbers 7:9

9But to the sons of Kohath he gave none, because they were charged with athe service of the holy things that bhad to be carried on the shoulder.

1 Chronicles 23:27-28

27For by the last words of David the sons of Levi were numbered from ctwenty years old and upward. 28For their duty was to assist the sons of Aaron for the service of the house of the Lord, having the care of the courts and the chambers, the cleansing of all that is holy, and any work for the service of the house of God.
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