Numbers 18:4

And they shall be joined unto thee ,.... As assistants in the sacred service:

and keep the charge of tabernacle of the congregation, for all the service of the tabernacle ; See Gill on Numbers 3:7 and See Gill on Numbers 3:8 ,

and a stranger shall not come nigh unto you ; not any of the other tribes, only such as were of the tribe of Levi; they only were to be brought with them, and joined unto them, and assist them, and minister to them, as in Numbers 18:2 ; though the Jews F8 Maimon. in Misn. Zebachim, c. 2. sect. 1. understand by a stranger anyone that was not a priest.