1 Chronicles 23:1-5

When David got to be an old man, he made his son Solomon king over Israel. At the same time he brought together all the leaders of Israel, the priests, and the Levites. The Levites thirty years and older were counted; the total was thirty-eight thousand. David sorted them into work groups: “Twenty-four thousand are in charge of administering worship in the sanctuary; six thousand are officials and judges; four thousand are security guards; and four thousand are to serve in the orchestra, praising GOD with instruments that I have provided for praise.”