4 Types of work for Levites as set out by King David

1 Chronicles 23:1-5

When David was old and full of years, he made his son Solomon king over Israel. He also gathered together all the leaders of Israel, as well as the priests and Levites. The Levites thirty years old or more were counted, and the total number of men was thirty-eight thousand. David said,

"Of these, twenty-four thousand are to be in charge of the work of the temple of the Lord

and six thousand are to be officials and judges.

Four thousand are to be gatekeepers

and four thousand are to praise the Lord with the musical instruments I have provided for that purpose."