John Calvin on Numbers 3:1-4

1. These also are the generations of Aaron and Moses He now separately enumerates the Levites; but, before he proceeds to state their number, he first shortly refers to what he had just before more fully narrated, that of the four sons of Aaron only two survived their father, inasmuch as Nadab and Abihu had suffered the penalty of their negligence in their defilement of the sacrifice. The six verses Viz., verses 5-10. See ante, vol. 2, p. 220. which Moses inserts respecting the office of the priests have been expounded in their proper place. The dignity of the tribe of Levi is here exalted, when God compares the Levites to the first-born; the distribution of their charges is also touched upon, “Quant a ce que Moyse touche ici des charges particulieres de chacune famille, combien que cela concerne le service duquel il a este traitte sur le Seconde Precepte, toutefois je n’ay peu aucunement faire, que de la mettre ici, afin que le fil de l’histoire ne fust point rompu;” with respect to the reference here made by Moses to the peculiar charge of each family, although it relates to the service which has been treated of under the Second Commandment, nevertheless I could not do otherwise than introduce it here, in order that the thread of the history might not be interrupted. — Fr. but, since these things are connected with the census of the people, and the mode of pitching the camp, I have thought it best to annex them to what has just preceded, inasmuch as otherwise the history would be interrupted. And, in fact, in the order that I have followed, the office of each family is only incidentally treated of, so that all might know their proper station.