Numbers 18:21-23

American Standard Version

²¹ And unto the children of Levi, behold, I have given all the tithe in Israel for an inheritance, in return for their service which they serve, even the service of the tent of meeting. ²² And henceforth the children of Israel shall not come nigh the tent of meeting, lest they bear sin, and die. ²³ But the Levites shall do the service of the tent of meeting, and they shall bear their iniquity: it shall be a statute for ever throughout your generations; and among the children of Israel they shall have no inheritance.