1 Chronicles 24:5
Thus were they divided by lot, one sort with another; for the governors of the sanctuary, and governors of the house of God, were of the sons of Eleazar, and of the sons of Ithamar. Thus were they divided by lot, one sort with another; for the governors of the sanctuary, and governors of the house of God, were of the sons of Eleazar, and of the sons of Ithamar.
David governed Israel by carefully apportioning special duties to the men best fitted for them. This plan was brought to perfection when Solomon was placed on the throne in the organization of the priests and Levites, the civil officers, and the army. The priests were divided by lot into twenty-four courses, and a full and accurate record of the division was made. Each course was thoroughly organized under its chief and came to Jerusalem twice a year to attend for one week to the ministry of the sanctuary.