Exodus 28:42-43

Lexham English Bible

⁴² And make for them undergarments of linen to cover naked flesh; they will be from loins to thigh. ⁴³ And they will be on Aaron and on his sons when they come to the tent of assembly or when they approach the altar to serve in the sanctuary, so that they will not bear guilt and die. It is a lasting statute for him and for his offspring after him.