He is to wear the sacred linen tunic, with linen undergarments. He must tie a linen sash around him and put on the linen turban. These are holy garments, and he must bathe himself with water before he wears them.
Here is, I. The date of this law concerning the day of atonement: it was after the death of the two sons of Aaron (Lev 16:1), which we read, Lev 10:1. 1. Lest Aaron should fear that any remaining guilt of that sin should cleave to his family, or (seeing the priests were so apt to offend) that some after-sin of his other sons should...
Commenting on Leviticus 16:1-4
He shall put on the holy linen coat,.... Which he wore in common with other priests: and he shall have the linen breeches upon his flesh; upon those parts of his body which are more secret, and less honourable flesh, meaning the same, as in Lev 15:2, and shall be girded with a linen girdle and with the linen mitre shall he be attired, as...
He shall put on the holy linen coat - He was not to dress in his pontifical garments, but in the simple sacerdotal vestments, or those of the Levites, because it was a day of humiliation; and as he was to offer sacrifices for his own sins, it was necessary that he should appear in habits suited to the occasion.