Numbers 8:19

And I gave the Levites presented as a gift to Aaron and his sons out of the midst of the children of Israel, to do the service of the children of Israel in the tabernacle of witness, and to make atonement for the children of Israel: thus there shall be none among the sons of Israel to draw nigh to the holy things.

And I have given the Levites as a gift to Aaron and to his sons from among the children of Israel, to do the service of the children of Israel in the tabernacle of the congregation, and to make an atonement for the children of Israel: that there be no plague among the children of Israel, when the children of Israel come nigh unto the sanctuary.

I have given the Levites as a gift to Aaron and to his sons from among the children of Israel, to do the service of the children of Israel in the Tent of Meeting, and to make atonement for the children of Israel, so that there will be no plague among the children of Israel when the children of Israel come near to the sanctuary.”