Even the principal fathers over against their younger brethren— The meaning, says Bishop Patrick, is, that both elder and younger had their places by lot, not by seniority of houses: they who were of greater dignity drew lots against those who were of less, and all were to take their courses according to the lot that they drew.
REFLECTIONS.—1st, The family of Eleazar, being most numerous, had sixteen courses; Ithamar only eight. That there might be no dispute about precedence, God appoints the determination of the order in which they should minister to be by lot: and these courses, though interrupted probably during the reigns of wicked kings, or in the captivity, yet subsisted still at their return, and till the destruction of the second temple. In Luke 1:5 we find John the Baptist's father of the course of Abijah, 1 Chronicles 24:10. Note; Order and regularity in God's worship must be carefully preserved.
2nd, The Levites, divided into the same number of courses as the priests, cast lots also to determine their order of service. When God determined their lot, there could be no room for strife. The priests are called their brethren, because, though the Levites were in a station inferior, yet they were employed in the same sacred service, and to be regarded, not as servants, but as assistants in their work.