John Gill Bible Commentary

And I will sanctify the tabernacle of the congregation, and the altar,.... This seems to intimate that something else in the preceding verse is intended, as what should be sanctified, than the tabernacle, as we supply it; or else here is a repetition of the same thing for the confirmation of it, and both that and the altar were, sanctified, or set apart for holy uses, as well as cleansed and expiated by sacrifices: I will sanctify also both Aaron and his sons, to minister to me in the priest's office; that is, in a ceremonial way, by separating them from the rest of the children of Israel, by washing, clothing, and anointing them, and by accepting sacrifices offered by them; for this is not to be understood of internal sanctifying grace, which, though Aaron had, and many of his sons that succeeded him, yet not all; nor was it necessary to the performance of the priestly office, though it is in all those who are a royal priesthood, and made priests as well as kings unto God; for they are a holy nation, called with an holy calling, and unto himself, and have it both internally and externally.