Luke 1:5

In the reign of Herod, King of Judea, there was a certain priest, named Zachariah, belonging to the class of Abijah. He had a wife named Elizabeth,

Luke 1:8

Now while Zachariah was acting as priest before God in the due course of his class, it fell to his lot, according to the custom of priesthood,

Acts 13:22

After deposing him, he raised up David to be their king, to whom he also bore witness, when he said, "I have found David, the son of Jesse, a man after my own heart, and who will obey all my will.

Acts 13:36

"For David, after he had served his own generation according to the will of God, fell on sleep, and was gathered to his forefathers, and did see corruption;

Treasury of Scripture Knowledge

Summary

And he appointed, according to the order of David his father, the courses of the priests to their service, and the Levites to their charges, to praise and minister before the priests, as the duty of every day required: the porters also by their courses at every gate: for so had David the man of God commanded.

The courses

So had david the man of god commanded

Bible References

The courses

Luke 1:5
In the reign of Herod, King of Judea, there was a certain priest, named Zachariah, belonging to the class of Abijah. He had a wife named Elizabeth,

So had david the man of god commanded

Acts 13:22
After deposing him, he raised up David to be their king, to whom he also bore witness, when he said, "I have found David, the son of Jesse, a man after my own heart, and who will obey all my will.