Amram's descendants included Aaron, Moses, and Miriam. Aaron's sons included Nadab, Abihu, Eleazar, and Ithamar.

With respect to the descendants of Aaron, classes of service were organized for Nadab, Abihu, Eleazar, and Ithamar, the descendants of Aaron.

But Nadab and Abihu died before their father did, leaving no sons, so Eleazar and Ithamar became priests.

Along with Zadok, one of Eleazar's descendants, and Ahimelech, one of Ithamar's descendants, David organized their service according to their assigned responsibilities.

More leaders were located among Eleazar's descendants than among those of Ithamar, so sixteen leaders were appointed from the leaders of the ancestral households of Eleazar's descendants and eight from those of Ithamar.

They were chosen by impartial lottery, since there were trustees of the sanctuary and officers of God among both Eleazar's descendants and among Ithamar's descendants.

Nethanel's son Shemaiah, a Levitical scribe, made an official record of them for the king, the officers, Zadok the priest, Abiathar's son Ahimelech, and the heads of ancestral households of both the priests and the descendants of Levi. One ancestral house was chosen for Eleazar and one for Ithamar.