Exodus 28:41-43

New Catholic Bible

⁴¹ Put these garments on Aaron, your brother, and his sons. Then anoint them and ordain them and consecrate them, so that they may serve as priests in my honor.

⁴² “Make linen undergarments to cover their nakedness. They must reach from their hips to their thighs. ⁴³ Aaron and his sons will put them on whenever they enter into the meeting tent or when they approach the altar to minister in the sanctuary, so that they may not incur guilt and die. This shall be a perpetual statute for him and his offspring forever.