1 Chronicles 24:3 in the King James Version
And David distributed them, both Zadok of the sons of Eleazar, and Ahimelech of the sons of Ithamar, according to their offices in their service.
Context
2 But Nadab and Abihu died before their father, and had no children; therefore Eleazar and Ithamar served as priests.
3 David, with Zadok of the sons of Eleazar and Ahimelech of the sons of Ithamar, divided them according to their ordering in their service.
4 There were more chief men found of the sons of Eleazar than of the sons of Ithamar; and they were divided like this: of the sons of Eleazar there were sixteen, heads of fathers’ houses; and of the sons of Ithamar, according to their fathers’ houses, eight.