Levi was God's tribe, a tribe that was to have no inheritance with the rest in the land of Canaan, and therefore was not numbered with the rest, but by itself; so it had been numbered in the beginning of this book at Mount Sinai, and therefore came not under the sentence passed upon all that were then numbered, that none of them should enter Canaan but Caleb and Joshua; for of the Levites that were not numbered with them, nor were to go forth to war, Eleazar and Ithamar, and perhaps others who were above twenty years old then (as appears, Numbers 4:16), entered Canaan; and yet this tribe, now at its second numbering, had increased but 1000, and was still one of the smallest tribes.
Mention is made here of the death of Nadab and Abihu for offering strange fire, as before of the sin and punishment of Korah, because these things happened to them for ensamples.