The old testament is filled with rituals that were ment to guide our relationship with God. There was many priests who would serve to mediate between God and man. There were various sacrifices that were made to atone for sin. All of this was a shadow of what was to come.
The book of Hebrews was written so the we can see that Jesus Christ, God’s Son, has not just come to fit into the earthly system of priestly ministry. He was not just a mere prophet. He wasn’t just the best and final human priest or just a significant sacrifice.
Jesus came to fulfill and put an end to that system of constant sacrifice. There is no need for priests to mediate for us because Jesus himself is ministering for us in heaven. The Old Testament tabernacle and priests and sacrifices were shadows. Now the reality has come, and the shadows pass away.
That’s what Christmas is. Christmas is the replacement of shadows with the real thing. Jesus.
Now the main point in what has been said is this:
we have such a high priest, who has taken His seat
at the right hand of the throne of the Majesty in the
heavens, a minister in the sanctuary, and in the true
tabernacle, which the Lord pitched, not man.
(This was inspired in part by John Pipers advent-Good news of Great Joy)