Daily courses
Archimandrite Nikifor’s Biblical Encyclopedia
(1 Chron. 24:3; 2 Chron. 8:14) — the division made by David of the Levites and priests for the performance of the priestly service. The priests were divided into 24 courses, each of which served in the Temple for a week, from Sabbath to Sabbath. To determine which priest received which course for a given day’s service, lots were customarily drawn (Luke 1:9). The Levites were divided into four classes (1 Chron. 24:1), but, according to Josephus, for their service in the sanctuary they were divided into 24 classes, each of which, like the priests, served by the week. The courses of the priests and Levites, according to their assignment, were reestablished by Hezekiah (2 Chron. 31:2) and afterward by Ezra (Ezra 6:18).