Here He says Christians have not come to the Heavenly Jerusalem and Zion;
You really don't see the truth of this passage do you? It is clouded by the allegorism of Calvinistic interpretation, the indoctrination of an over-zealous Covenantal theology so much so that you can't see the forest for the trees.
Consider:
Heb 12:21 And so terrible was the sight, that Moses said, I exceedingly fear and quake)
Heb 12:22 But ye are come unto mount Sion, and unto the city of the living God, the heavenly Jerusalem, and to an innumerable company of angels,
Heb 12:23 To the general assembly and church of the firstborn, which are written in heaven, and to God the Judge of all, and to the spirits of just men made perfect,
Remember the over-all context. The author is addressing Hebrews who were discouraged through persecution, some of whom were wanting to return to the old system of Temple worship. Paul sets before them these two systems: the Old and the New. They are constantly contrasted throughout the entire book.
The key words are "better than" or "Let us..." as in "let us go on"
Here is the contrast between the law, the nation being delivered from Egypt and coming to Mount Sinai where they are made a theocracy and given the Law of Moses. It was fearful to come right before that very mount before the presence of God. Only Moses could go into the mount itself. The entire scene was terrifying. Moses himself trembled. (Vs. 21: "I exceedingly fear and quake."
By contrast: vs 22 "BUT"
But ye are come unto mount Sion, and unto the city of the living God, the heavenly Jerusalem, and to an innumerable company of angels,
--They have not come to such a forbidding and terrifying place, but rather a place where there is grace and mercy. Every believer can enter this place by faith. We can approach the living God by faith: in confession, praise, prayer.
Then the High Priest entered in once a year.
We can enter in at any time.
The law had it its Mount Sinai
Mont Zion is a heavenly mountain that symbolizes all the blessings that we receive by faith. They are ours because of the grace of our Lord Jesus Christ.
The Law had its earthly Jerusalem, but faith has its heavenly capital above.
It is the city of the living God.
We are strangers and pilgrims on this earth. (Phil.3:20). Someday we will enter into that city but not now. We only see it by faith. It is a real city.
Today we are members of the bride of Christ, the family of God, all who have died since Pentecost. Those who have died are in the presence of Christ awaiting the resurrection. We also await the resurrection, the redemption of our bodies.
By faith we see God the Judge of all. Someday we will meet him. We will stand before him.
Heb 12:23 To the general assembly and church of the firstborn, which are written in heaven, and to God the Judge of all, and to the spirits of just men made perfect,
--But this place we look to in faith. We have not attained there yet. Someday we will. Not now. We look in faith. We have not attained.
We do not stand before the Judge.
We are not with "the spirits of just men made 'complete'"
We are not there yet.