Leviticus 16:30

30. To cleanse you This cleansing was, 1.) a restoration of the worshipper to membership and communion with the congregation of Israel; and, 2.) the pretermission or Old Testament forgiveness of sins to the penitent believer in the divine promises. For we cannot admit that there was in the Jewish sacraments an operation of grace propria virtute, that is, by themselves alone, irrespective of the spiritual state of the worshipper. “The perfection of the worshippers is the complete restoration of their peace with God; and this only can be attained by the complete removal of the barrier formed by sin, by making them in the fullest sense cleansed.

Had this ever really been once effected for the congregation of Israel by the annual sacrifices of the day of atonement, no need would have been felt for a repetition of them. But this was not so.” Delitzsch on Hebrews 10:2. See Introduction, (7.)