The tenth For the tithes were all given to the Levites, and out of their tithes the tenth was given to the priests. Come nigh the tabernacle So nigh as to do any proper act to the priests or Levites.
Related Commentaries of Numbers 18:21
Numbers 18:21-22
21 And, behold, I have given the children of Levi all the tenth in Israel for an inheritance, for their service which they serve, even the service of the tabernacle of the congregation.
22 Neither must the children of Israel henceforth come nigh the tabernacle of the congregation, lest they bear sin, and die.b