For the Lord had spoken unto Moses
Not to number the Levites, when he gave him the orders to number the rest of the tribes: this is observed, lest it should be thought that this was what Moses did of himself, out of affection to the tribe he was of, and to spare it, that it might not be obliged to go forth to war when others did; not that they were forbid to engage in war, or that it was unlawful for them so to do, for when necessity required, and they were of themselves willing to engage in it, they might, as appears in the case of the Maccabees, but they might not be forced into it; they were, as Josephus
F5 Antiqu. l. 3. c. 12. sect. 4.