The Sefarno notes the possible question that the Torah specifies Aharon, the Kohen Gadol, as being the one to arrange the lamps, since an ordinary Kohen is also qualified to do so. The same question can be asked on the verse from Shmos 30,7 regarding the burning of incense, where Aharon is also specifically mentioned as being in charge.
The Seforno explains that throughout the years in the midbar, the Mishkan had the status of Yom Kippur every day. The exalted level of Yom Kippur is described in the beginning of the parsha: “For in a cloud I will appear.” The pasuk at the end of Chumash Shemos21 informs us that the Mishkan in the Wilderness had a cloud hovering over it constantly! Therefore, says the Seforno, in the same way that on Yom Kippur, all parts of the avodah are performed specifically by the Kohen Gadol, so too, on a daily basis during those forty years; therefore, the pasuk states that “Aharon” specifically should offer the ketores and light the menorah.
