They are to perform duties for him and for the whole congregation before the Tent of Meeting, attending to the service of the tabernacle.
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 they shall keep his charge, and the charge of the whole congregation,.... The charge of Aaron and of all the people of Israel, which was to secure the sanctuary from being polluted or plundered: this the Levites were to be employed about, and thereby ease the high priest and the other priests, and the people, of what otherwise would have been incumbent on them...
And they shall keep his charge, and the charge of the whole congregation before the tabernacle of the congregation, to do the service of the tabernacle. (e) Which belonged to the executing of the high priests commandment, to the oversight of the people, and the service of the tabernacle.