And David distributed them. — The same phrase as at 1 Chronicles 13:3. (See Note there.)
Both Zadok of the sons of Eleazar, and Ahimelech of the sons of Ithamar. — This expression forms part of the subject of the Hebrew sentence. The construction is like that in 1 Chronicles 24:2, “And Nadab died, and Abihu.” Thus, “And David divided them, and Zadok and Ahimelech,” i.e., “And David, with Zadok and Ahimelech, divided them.” The meaning is that Zadok and Ahimelech, the heads of the houses of Eleazar and Ithamar, assisted David in the classification of the priests.
According to their offices. — Rather, According to their official class (1 Chronicles 23:11).