Exodus 28:1

And take thou unto thee Aaron thy brother— The house and the more material parts of the furniture being provided, Jehovah next appoints the ministers of that house, and by a solemn consecration sets apart Aaron and his sons. What we read, that he may minister unto me, should certainly be read, according to the Samaritan and others, that they may minister unto me. There cannot be the least doubt that there were priests among the Hebrews before this time, as we have had occasion frequently to remark in the course of our notes; see, particularly, ch. Exodus 19:22; Exodus 19:24.