Nadab and Abihu, however, died in the presence of the LORD when they offered unauthorized fire before the LORD in the Wilderness of Sinai. And since they had no sons, only Eleazar and Ithamar served as priests during the lifetime of their father Aaron.
Here, I. The family of Aaron is confirmed in the priests' office, Num 3:10. They had been called to it before, and consecrated; here they are appointed to wait on their priests' office: the apostle uses this phrase (Rom 12:7), Let us wait on our ministry.
Commenting on Numbers 3:1-13
And Nadab and Abihu died before the Lord,...., By flaming fire, as the Targum of Jonathan adds, see Lev 10:2; and so were not alive at this time when the account of the priests and Levites was taken: when they offered strange fire before the Lord in the wilderness of Sinai; after the tabernacle was set up, and the service of it begun, and quickly...
And Nadab and Abihu died before the LORD, when they offered strange fire before the LORD, in the wilderness of Sinai, and they had no children: and Eleazar and Ithamar ministered in the priest's office in the sight of Aaron their father. (b) Or, before the altar. (c) While their father lived.