And David organized them in divisions corresponding to the sons of Levi: Gershon, Kohath, and Merari.
2 Chronicles 8:14
According to the ruling of David his father, he appointed the divisions of the priests for their service, and the Levites for their offices of praise and ministry before the priests as the duty of each day required, and the gatekeepers in their divisions at each gate, for so David the man of God had commanded.
1 Chronicles 6:1
The sons of Levi: Gershon, Kohath, and Merari.
Ezra 6:18
And they set the priests in their divisions and the Levites in their divisions, for the service of God at Jerusalem, as it is written in the Book of Moses.
2 Chronicles 29:25
And he stationed the Levites in the house of the Lord with cymbals, harps, and lyres, according to the commandment of David and of Gad the king’s seer and of Nathan the prophet, for the commandment was from the Lord through his prophets.
1 Chronicles 6:16