Leviticus 16:23

For this ceremony, the high priest had to wear special clothing used only for this purpose (Leviticus 16:4). When the ceremony ended, he had to leave the garments in the Most Holy Place. Many scholars believe that bathing and changing clothes were necessary because handling the sin offering caused ceremonial uncleanness.

The day of atonement, on the tenth day of the seventh month, was the most serious and holy day of the year for Israelites (see Leviticus 16:29; 23:27; Numbers 29:7). It was the only required fast and a Sabbath of rest for all the people (Leviticus 23:32). The Feast of Trumpets came before it and announced its arrival (Numbers 29:1, 7–11). On this day, God forgave the sins of the community. Only the high priest, Aaron, could lead the ceremony because he represented all the people. This included Aaron’s sons, the other priests. Today, the Jews call the day of atonement Yom Kippur.

Aaron shall come into the tabernacle of the congregation, and shall put off the linen garments--On the dismissal of the scapegoat, the high priest prepared for the important parts of the service which still remained; and for the performance of these he laid aside his plain linen clothes, and, having bathed himself in water, he assumed his pontifical dress. Thus gorgeously attired, he went to present the burnt offerings which were prescribed for himself and the people, consisting of the two rams which had been brought with the sin offerings, but reserved till now. The fat was ordered to be burnt upon the altar; the rest of the carcasses to be cut down and given to some priestly attendants to burn without the camp, in conformity with the general law for the sin offerings (Lev 4:8-12; Lev 8:14-17). The persons employed in burning them, as well as the conductor of the scapegoat, were obliged to wash their clothes and bathe their flesh in water before they were allowed to return into the camp.

The high priest having presented unto the Lord the expiatory sacrifices, by the sprinkling of their blood, the remainder of which, it is probable, he poured out at the foot of the brazen altar, 1. He is next to confess the sins of Israel, with both his hands upon the head of the scape-goat (Lev 16:20, Lev 16:21); and whenever hands were imposed upon the head of any sacrifice it was always done with confession, according as the nature of the sacrifice was; and, this being a sin-offering, it must be a confession of sin. In the latter and more degenerate ages of the Jewish church they had a set form of confession prepared for the high priest, but God here prescribed none; for it might be supposed that the high priest was so well acquainted with the state of the people, and had such a tender concern for them, that he needed not any form. The confession must be as particular as he could make it, not only of all the iniquities of the children of Israel, but all their transgressions in all their sins. In one sin there may be many transgressions, from the several aggravating circumstances of it; and in our confessions we should take notice of them, and not only say, I have sinned, but, with Achan, "Thus and thus have I done." By this confession he must put the sins of Israel upon the head of the goat; that is, exercising faith upon the divine appointment which constituted such a translation, he must transfer the punishment incurred from the sinners to the sacrifice, which would have been but a jest, nay, an affront to God, if he himself had not ordained it. 2. The goat was then to be sent away immediately by the hand of a fit person pitched upon for the purpose, into a wilderness, a land not inhabited; and God allowed them to make this construction of it, that the sending away of the goat was the sending away of their sins, by a free and full remission: He shall bear upon him all their iniquities, Lev 16:22. The losing of the goat was a sign to them that the sins of Israel should be sought for, and not found, Jer 50:20. The later Jews had a custom to tie one shred of scarlet cloth to the horns of the goat and another to the gate of the temple, or to the top of the rock where the goat was lost, and they concluded that if it turned white, as they say it usually did, the sins of Israel were forgiven, as it is written, Though your sins have been as scarlet, they shall be as wool: and they add that for forty years before the destruction of Jerusalem by the Romans the scarlet cloth never changed colour at all, which is a fair confession that, having rejected the substance, the shadow stood them in no stead. 3. The high priest must then put off his linen garments in the tabernacle, and leave them there, the Jews say never to be worn again by himself or any other, for they made new ones every year; and he must bathe himself in water, put on his rich clothes, and then offer both his own and the people's burnt-offerings, Lev 16:23, Lev 16:24. When we have the comfort of our pardon God must have the glory of it. If we have the benefit of the sacrifice of atonement, we must not grudge the sacrifices of acknowledgment. And, it should seem, the burning of the fat of the sin-offering was deferred till now (Lev 16:25), that it might be consumed with the burnt-offerings. 4. The flesh of both those sin-offerings whose blood was taken within the veil was to be all burnt, not upon the altar, but at a distance without the camp, to signify both our putting away sin by true repentance, and the spirit of burning, and God's putting it away by a full remission, so that it shall never rise up in judgment against us. 5. He that took the scape-goat into the wilderness, and those that burned the sin-offering, were to be looked upon as ceremonially unclean, and must not come into the camp till they had washed their clothes and bathed their flesh in water, which signified the defiling nature of sin; even the sacrifice which was but made sin was defiling: also the imperfection of the legal sacrifices; they were so far from taking away sin that even they left some stain upon those that touched them. 6. When all this was done, the high priest went again into the most holy place to fetch his censer, and so returned to his own house with joy, because he had done his duty, and died not.

And when he hath made an end of reconciling. The mode of expiation with the other goat is now more clearly explained, viz., that it should be placed before God, and that the priest should lay his hands on its head, and confess the sins of the people, so that he may throw the curse on the goat itself. This, as I have said, was the only bloodless (anaimaton) sacrifice; yet it is expressly called an "offering," [248] with reference, however, to the slaying of the former goat, and was, therefore, as to its efficacy for propitiation, by no means to be separated from it. It was by no means reasonable that an innocent animal should be substituted in the place of men, to be exposed to the curse of God, except that believers might learn that they were in no wise competent to bear His judgment, nor could be delivered from it otherwise than by the transfer of their guilt and crime. For, since men feel that they are altogether overwhelmed by the wrath of God, which impends over them all, they vainly endeavor to lighten or shake off in various ways this intolerable burden; for no absolution is to be hoped for save by the interposition of a satisfaction; and it is not lawful to obtrude this according to man's fancy, or, in their foolish arrogance, to seek in themselves for the price whereby their sins may be compensated for. Another means, therefore, of making atonement to God was revealed when Christ, "being made a curse for us," transferred to Himself the sins which alienated men from God. (2 Corinthians 5:19; Galatians 3:13.) The confession tended to humiliate the people, and thus acted as a stimulus to sincere repentance; since "the sacrifices of God are a broken spirit," (Psalm 51:17;) nor is it fit that any but the prostrate should be lifted up by God's mercy, nor that any but those who voluntarily condemn themselves should be absolved. The accumulation of words tends to this, "all the iniquities, all their transgressions, all their sins," that believers may not lightly only and as, a mere act of duty acknowledge themselves guilty before God, but rather that they should groan under the weight, of their guilt. Since now in Christ no special day in the year is prescribed in which the Church should confess its sins in a solemn ceremony, let believers learn, whenever they meet together in God's name, humbly to submit themselves to voluntary self-condemnation, and to pray for pardon, as if the Spirit of God dictated a formulary for them; and so let each in private: conform himself to this rule.

Aaron shall lay both his hands upon the head, etc. - What this imposition of hands meant see in the notes on Exo 29:10 (note), and Lev 1:4 (note).
And confess over him all the iniquities - transgressions - sins - The three terms used here, Iniquities, עונת avonoth, from עוה avah, to pervert, distort, or turn aside; Transgressions, פשעים peshaim, from פשע pasha, to transgress, to rebel; and Sins, חטאת chattaoth, from חטא chata, to miss the mark, are supposed by the Jews to comprise every thing that implies a breach of the Divine law, or an offense against God. See Clarke's note on Gen 12:13. Maimonides gives us the confession in the following words: -
"O Lord, thy people, the house of Israel, have sinned and done iniquity, and trespassed before thee. O Lord, make atonement now for the iniquities and transgressions and sins that thy people, the house of Israel, have sinned and transgressed against thee; as it is written in the law of Moses thy servant, saying: That in this day he shall make atonement for you, to cleanse you from all your sins before the Lord, and ye shall be clean." - See the Mishna, vol. ii., p. 329. When this confession was finished, the goat was sent by a proper hand to the wilderness, and there let loose; and nothing farther was ever heard of it. Did not all this signify that Christ has so carried and borne away our sins, that against them who receive him as the only true atoning sacrifice they should never more be brought to remembrance? On the head of the scape-goat, a piece of scarlet cloth was tied, and the tradition of the Jews states that if God accepted the sacrifice, the scarlet cloth turned white while the goat was led to the desert; but if God had not accepted this expiation, the redness continued, and the rest of the year was spent in mourning. From the foundation of the Church of God it was ever believed by his followers, that there were certain infallible tokens by which he discovered to genuine believers his acceptance of them and their services. This was sometimes done by a fire from heaven consuming the sacrifice; sometimes by an oracular communication to the priest or prophet; and at other times, according to the Jewish account, by changing the fillet or cloth on the head of the scape-goat from scarlet to white: but most commonly, and especially under the Gospel dispensation, he gives this assurance to true believers by the testimony of his Spirit in their consciences, that he has forgiven their iniquities, transgressions, and sins, for his sake who has carried their griefs, and borne their sorrows.

And Aaron shall come into the tabernacle of the congregation,.... Having been into the most holy place a fourth time, as the Jews say, to fetch out the censer and the incense cup; wherefore the Jewish writers observe, that this verse is not in its proper place; so Jarchi from the Rabbins says, the whole section is in its order, excepting this, which was after the sacrifice of his burnt offering, and the burnt offering of the people; and the burning the inwards of the bullock and the goat, which were done without in the golden garments; and then he dipped himself, and washed his hands and feet, and stripped and put on the white garments, and went in to fetch the incense cup and the censer, with which he offered in the inmost place (the holy of holies):

and shall put off the linen garments which he put on when he went into the holy place; the holy of holies, that is, as Jarchi interprets it, after he had brought it (the censer) out, then he clothed himself with the golden garments for the daily evening sacrifice; and this was the order of the services (on the day of atonement); the daily morning sacrifice (was performed) in the golden garments; the service of the bullock and of the goat, and the incense of the censer, in the white garments; and his ram, and the ram of the people, and some of the additions, in the golden garments; and the bringing out of the incense cup and the censer in the white garments; and the rest of the additions, and the daily evening sacrifice, and the incense of the temple, on the inward altar, in golden garments; and the order of the Scripture, according to the services, so it was:

and shall leave them there; in one of the chambers of the tabernacle, as afterwards, in the temple, where they were laid up, never to be used more, as say the Jewish writers, Ben Gersom, and others; hence we learn, says Jarchi, that they were obliged to be laid up, and he, the high priest, might not minister in these four garments on another day of atonement.

Aaron shall come, forthwith, not expecting the return of the man who carried the goat away, but securely committing that to God’ s providence he shall go on in his work.

After the living goat had been sent away, Aaron was to go into the tabernacle, i.e., the holy place of the dwelling, and there take off his white clothes and lay them down, i.e., put them away, because they were only to be worn in the performance of the expiatory ritual of this day, and then bathe his body in the holy place, i.e., in the court, in the laver between the altar and the door of the dwelling, probably because the act of laying the sins upon the goat rendered him unclean. He was then to put on his clothes, i.e., the coloured state-dress of the high priest, and to offer in this the burnt-offerings, for an atonement for himself and the nation (see Lev 1:4), and to burn the fat portions of the sin-offerings upon the altar.