Leviticus 16:24

He shall put on his linen garments — Not his ordinary priestly linen garments, for he was to leave them in the tabernacle, Leviticus 16:23, but the high — priestly garments, called his garments properly, and by way of distinction. And this change of his garments was not without cause. For the common priestly garments were more proper for him in the former part of his ministration, both because he was to appear before the Lord in the most holy place to humble himself and make atonement for his own and for the people's sins, and therefore his meanest attire was most fit, and because he was to lay his hands upon that goat on which all their sins were put, by which touch both he and his garments would be in some sort defiled, and therefore as he washed himself, so we may presume his linen garments were laid by for the washing, as the clothes of him who carried away the scape — goat were washed, Leviticus 16:26. And the high — priestly garments were most proper for the latter part of his work, which was of another nature.