Leviticus 16:23-34
See how great and how intricate for the high priest and his sons was the work necessary for taking away sins. Then again all this service was only effective for one year. In fact the source of the sins, the heart of man, was not cleansed even for a year, and this wicked heart could not fail still to produce wicked actions throughout the new year. It was always necessary to repeat these sacrifices over again, the high priest handing down his office from father to son "because they were not suffered to continue by reason of death" (Hebrews 7:23-25).
How much greater is the work of Christ in all its reality, in all its scope, demanding the sacrifice of Himself! In order to take away the sin of the world, to cancel all its consequences, but also to reach its source — the heart of man — and to cleanse it, Jesus has "an unchangeable priesthood". No one else can have the smallest share in His work. What were the people doing during this great work of the high priest? They could not and should not do anything except afflict their souls. A work was accomplished on their behalf on which they rested. Well, that also is all you have to do, dear reader: rest upon the all-sufficient and perfect work of the Lord Jesus.