exodus 29:1 And this is the thing that thou shalt do unto them to hallow them, to minister unto me in the priest's office: Take one young bullock, and two rams without blemish, - Free Bible Online

      Ex 29:1-35. CONSECRATING THE PRIESTS AND THE ALTAR.

      1. hallow them, to minister unto me in the priest's office--The act of inaugurating the priests was accompanied by ceremonial solemnities well calculated not only to lead the people to entertain exalted views of the office, but to impress those functionaries themselves with a profound sense of its magnitude and importance. In short, they were taught to know that the service was for them as well as for the people; and every time they engaged in a new performance of their duties, they were reminded of their personal interest in the worship, by being obliged to offer for themselves, before they were qualified to offer as the representatives of the people.
      this is the thing that thou shalt do--Steps are taken at the beginning of a society, which would not be repeated when the social machine was in full motion; and Moses, at the opening of the tabernacle, was employed to discharge functions which in later periods would have been regarded as sacrilege and punished with instant death. But he acted under the special directions of God.

JFB.