Levi — Because they were not generally to go out to war, which was the thing principally eyed in this muster, Numbers 1:3, Numbers 1:20, Numbers 1:45, but were to attend upon the service of the tabernacle. They that minister upon holy things, should not entangle themselves in secular affairs. The ministry itself is work enough for a whole man, and all little enough to be employed in it.
Related Commentaries of Numbers 1:49
Numbers 1:49
49 Only thou shalt not number the tribe of Levi, neither take the sum of them among the children of Israel: