Mtn vs Mtn

Hebrews 12:18-27

Here the author compares two mountains. The first, without being names, is obviously Mt. Sinai, where the law was given to Moses. The second is Mt. Zion where the city of Jerusalem rests. The author seems to be revisiting the theme of the supremacy of Christ: Christ is superior because the mountain of the new covenant (Zion) is superior to the mountain of the old covenant (Sinai). The differences are that Mt Sinai is a physical mountain while Mt Zion is spiritual, Mt Sinai is filled with darkness, mystery and death while Mt. Zion is filled with light, joy and life.
The author makes a list of things we have come to: Mount Zion, thousands upon thousands of angels, the church of the firstborn, to God, to the spirits of the righteous (a reference to the great cloud of witnesses?), to Jesus and to the sprinkled blood that speaks a better word than the blood of Abel. This is an interesting phrase. Abel's blood cried out from the ground to the ear of God and the implied cry was a cry for justice. Justice demanded that someone pay for his murder. Jesus' blood cries out that justice has already been satisfied. When I sin and then truly repent, Jesus' blood cries out on my behalf. The word is the same (justice!) but the implications are very different.
Through the blood of Jesus the curse has been removed. I now approach God with full confidence by the blood of Jesus. My relationship to God is no longer based on law and death but on grace and life. I can join the thousands upon thousands of angels in their joyful assembly and the church of the firstborn because I am being made perfect by of the sacrifice of Christ. I claim the sprinkled blood that speaks a better word...

Written in Blood

Hebrews 9:16-28

This is a longer section where the author talks about the necessity of death to bring a will or covenant into effect. He points to the old covenant which was only put into effect by the blood of animals. Moses sprinkled the scroll, the people, the tabernacle and everything in it. The author concludes that without the shedding of blood there can be no forgiveness.
If the copies of the heavenly things were cleansed through animal sacrifice, then a greater and better sacrifice is necessary for the heavenly things to be consecrated. Jesus' sacrifice is superior to the sacrifices offered under the Mosaic covenant because Jesus sacrifice consecrates the real tabernacle in heaven, not just its earthly copies and because Jesus sacrifice stands for all time, unlike the constant animal sacrifices necessary under the Mosaic covenant.
The author's is using a very hebraic logical argument which, in overly simplistic terms, sort of looks like a wheel: the main point is the hub and the arguments which prove the main point are the spokes. Rather than following one spoke all the way to argue for the main point, the hebraic logical argument moves around the wheel from spoke to spoke gradually making its way to the center. If we were to re-write Hebrews to fit a western (or greek) logical argument, we would state our main idea (the supremacy of Christ and then we would take all the sections about Christ's priesthood being superior to the Aaronic priesthood and put them all in the same spot and then take all the arguments about Christ's sacrifice being greater than the sacrifices of the tabernacle and put them all in the same spot, and then all the arguments about the heavenly tabernacle where Christ serves as being superior to the earthly tabernacle where the priests serve and put them all at the same spot, etc.
Because of the hebraic construct of this book, we find elements of all those arguments in this section. In our minds it seems repetitive, which it is but each time the author revisits or incorporates one of the spokes, it is explored more fully with the goal of moving the reader ever inward towards the conclusion that Christ is superior to anything in the old system and covenant.