Bible Verses About Priests: Worn always while engaged in the service of the tabernacle

Aharon and his sons are to wear them when they go into the tent of meeting and when they approach the altar to minister in the Holy Place, so that they won't incur guilt and die. This is to be a perpetual regulation, both for him and for his descendants.

the garments for officiating, for serving in the Holy Place; the holy garments for Aharon the cohen; and the garments for his sons to serve in the office of cohen.