1 Chronicles 24:3-5

David, with Zadok of the sons of Eleazar and Ahimelech of the sons of Ithamar, divided them according to their offices for their assigned duties. Since there were more chief men found among the descendants of Eleazar than among the descendants of Ithamar [because of Eli’s misfortunes, and Saul’s massacre of the priests at Nob], they were divided in this way: sixteen heads of fathers’ households of the descendants of Eleazar and eight of the descendants of Ithamar, corresponding to their fathers’ households. So they were divided by lot, one group with the other; for they were officers of the sanctuary and officers (high priests) of God, both from the descendants of Eleazar and from the descendants of Ithamar.