1 Chronicles 24:1

In this chapter we find the divisions of the priests. First comes the one thing Chronicles is never without: God has fully judged the flesh and set it aside in the person of Nadab and Abihu. Then come Eleazar and Ithamar. Because Eli and his sons were unfaithful, Ithamar loses his first place under the reign of David and Solomon, and later under Christ's thousand-year reign. Yet the priesthood is not taken away from him (v. 3). Eleazar takes first place through Zadok, who came from him, because of Phinehas' zeal… Solomon drove Abiathar, who came from Ithamar, out of the priesthood (1 Kings 2:26), but Chronicles does not mention this. Here we find the priesthood, like the kingship, established according to God's counsels.

After Nadab and Abihu come Eleazar and Ithamar. Eleazar is the priest chosen by grace. Ithamar is the responsible priest, set aside to make room for Eleazar.

Abihu and Nadab, sons of Aaron, with seventy of the elders of Israel, were invited to go up with Moses. There they saw God, and ate and drank (Exodus 24:1, 9-11). They were set apart to serve the Lord as priests. Yet the first time they acted as priests for Israel, they offered strange fire, which the Lord had not commanded. Fire from God struck them dead (Leviticus 10:1-2)… The case of Nadab and Abihu should teach us that not every kind of worship is acceptable to God: "those who worship him must worship in spirit and truth" (John 4:24). Outward worship alone will not do. It must be according to what God has revealed.

The two who died under judgment, almost as soon as they were consecrated as priests, had no excuse for their sin. They fell despite this great privilege. Eleazar and Ithamar, who carried on as priests, do not seem to have had this unique experience. Failure is often most marked in those who are most highly privileged.

There were sixteen heads of fathers' houses in Eleazar's family and eight in Ithamar's… It was the will of God, and not the will of man, that set them in their courses. Before the gift of the Holy Spirit, the lot was the sign that God stepped in directly, without man's will (Acts 1:26; Luke 1:9)… so that the sons of Eleazar had a double portion. So there were twenty-four groups of priests according to God's thought.

David set up the twenty-four courses of the priesthood, as recorded in 1 Chronicles 24, and the course of Abia (or Abijah) was the eighth. In the time of the Gospels each course served as priests in the temple of the Lord for one week at a time… On any given day, four lots were cast for both the morning and the evening sacrifices. These lots chose the individual priests to prepare the altar, to kill the sacrifice, to offer the incense, and finally to burn the sacrifice on the altar. The third lot, to offer the incense, was the one priests wanted most, and it could fall to a priest only once in his lifetime. This was the lot which fell to Zacharias, on the great day when the angel of the Lord appeared and spoke to him about the birth of John the Baptist.

When David divided the priests into courses, he found twenty-four heads of the priestly families, so there were twenty-four courses. Those twenty-four heads therefore stood for the whole priesthood. In the same way, the twenty-four elders are taken to stand for the saints of this period. Scripture already works on this principle. They stand as well for all who are Christ's, the saints who share in the first resurrection.