Daily Aliya for Pekudei, Chamishi (5th Aliya)
Aliya Summary: G‑d instructed Moshe to erect the Tabernacle on the first of Nissan. G‑d also instructed Moshe to place all the Tabernacle’s vessels in their proper places, and to anoint all of the items with the anointing oil, thus sanctifying them. Moshe is also directed to dress Aaron and his sons in the priestly garments, and to anoint them, too.
Note that Aaron’s sons were also anointed. Regular kohanim are not; they were exceptions. It gave them a status of Kohen Gadol. That’s why Elazar and Itamar were not able to tend to the bodies of their brothers Nadav and Avihu and cousins were called in to take care of things. Aaron’s sons needed to be anointed, because they weren’t kohanim by birth.