6 David separated the Levites into divisions corresponding to the sons of Levi: Gershon, Kohath and Merari.

Read 1 Chronicles 23:6 Using Other Translations

And David divided them into courses among the sons of Levi, namely, Gershon, Kohath, and Merari.
And David organized them in divisions corresponding to the sons of Levi: Gershon, Kohath, and Merari.
Then David divided the Levites into divisions named after the clans descended from the three sons of Levi—Gershon, Kohath, and Merari.