1 Chronicles 24:3

24:3 David, Zadok (a descendant of Eleazar), and Ahimelech (a descendant of Ithamar) divided them into groups to carry out their assigned responsibilities.

1 Chronicles 24:19

24:19 This was the order in which they carried out their assigned responsibilities when they entered the Lord’s temple, according to the regulations given them by their ancestor Aaron, just as the Lord God of Israel had instructed him.