we are not in the same place in our understanding.
First the mystery kept hidden from past generations
Colossians 2. [brackets are mine]
....his body, that is the church of which I became a minister according to the divine office which was given me for you [Gentiles]
to make the word of God fully known, the mystery hidden for ages and generations but now made manifest to His saints [the Jews]
To them God chose to make known how great among the Gentiles are the riches of the glory of this mystery which is Christ IN YOU [Gentiles] the hope of glory.
I see your passage comes from Col 1:25-29.
If I understand correctly, you are proposing that "saints" refers to "Christians and nonChristians of Jewish heritage", and also proposing that the audience of Colossians would only be Christians of nonJewish heritage.
I don't agree with the interpretation that "saints" would mean only Jews. I don't agree with the interpretation that "saint" could include Jews that are not in Christ. I don't find the Dispensationalism framework to be compatible with the Bible.
"To the saints and faithful brethren in Christ which are at Colosse: Grace be unto you, and peace, from God our Father and the Lord Jesus Christ." - Col 1:2 KJV
The audience of the book of Colossians includes "saints". If Christians and nonChristians of Jewish heritage are "saints", that means that they are included in the audience. The "you" in Col 1:3-4 means that "saint" cannot be referencing nonChristian Jews.
"We give thanks to God and the Father of our Lord Jesus Christ, praying always for you, Since we heard of your faith in Christ Jesus, and of the love which ye have to all the saints," - Col 1:3-4 KJV
These lines even state "Grace be upon you" which makes perfect sense in Christianity but conflicts with the Dispensationalist position that "a dispensation of Grace" was somehow only meant for nonJews.
Saints (those set apart) are Christians, plain and simple. Saints belong to the body of Christ, the church.
"For God is not the author of confusion, but of peace, as in all churches of the saints." - 1 Cor 14:33 KJV
"To all that be in Rome, beloved of God, called to be saints: Grace to you and peace from God our Father, and the Lord Jesus Christ." - Rom 1:7 KJV
Ultimately, translating "saint" as "Christians and nonChristians of Jewish heritage" is untenable. Which means that your interpretation of Col 1 regarding divisions of "saints" vs the "you" audience is incoherent.
If we look at the meaning of saints, we see in Psalm 50 a reference to those thàt have a covenant with God through a sacrifice.
"Gather my saints together unto me; those that have made a covenant with me by sacrifice." - Psalm 50:5 KJV
"Above when he said, Sacrifice and offering and burnt offerings and offering for sin thou wouldest not, neither hadst pleasure therein; which are offered by the law; Then said he, Lo, I come to do thy will, O God. He taketh away the first, that he may establish the second. By the which will we are sanctified through the offering of the body of Jesus Christ once for all." - Heb 10:8-10 KJV
In a post crucifixion world, the only suitable sacrifice for a relationship with God is by accepting the sacrifice of Jesus Christ. "Saint" and "sanctification" are closely tied terms. All of those in Christ are saints and have entered that covenant by a blood sacrifice in Christ.
We always apply this Christ in us to ourselves as individuals for we are saved individually and that's right. But Paul in this instance is applying it to the Gentile church as it is planted among the nations of the world.
There is no such thing as "the Gentile church". There were churches that may have been led by Gentiles (cf. Rom 16:4), but not a Gentile 'church' distinctive from Jews. There is one body.
Churches "of" the Gentiles from the Greek can be understood as "churches within the foreign nations"
For the Jews the throne of David was to be set up and the nations of the world were to come to Jerusalem to learn the ways of the God of Jacob. So it shall be in the millennium.
A literal 1000 year kingdom is certainly one way to interpet Revelation.
The Dispensationalism 1000 year kingdom is heavily influenced by the Talmudic Judaic interpretation of the 1000 year kingdom. Talmudic Judaism is an antiChrist religion.
It is important to understand how sharp the contention was that sprang up between Peter and Paul, we pass over it too lightly. For Paul to withstand Peter to the face was a massive event, considering who Peter was the "Rock" upon who Christ was to "build His church"
Jesus rebuked Peter at one point with the infamous "get thee behind me, Satan". God was speaking through Paul to again rebuke and correct a wrong. It is wrong to divide the body of Christ by those of the Jews and those not of the Jews. The sequence is an important lesson to tell all Christians that "yes" you can carry forward many traditions of your forefathers, but not traditions that are incompatible with Christianity.
It fully shows the difference in understanding the gospel of grace Paul was preaching between the Jews and the Gentiles.
Paul was preaching to all parties of the church, those of Jew and Gentile origin alike.
No matter how many times in different ways God had been showing Peter that there was to be no distinction between Jews and Gentiles, he was still in the mind frame to withdraw from the Gentiles and treat them as unclean still.
The Dispensationist movement continues to try to withdraw those with Jewish heritage from the church. Where the word of Christ should be spread to the world, there are some Dispensationalists that have the opinion that Talmudic Jews don't need that message for some reason, or that Talmudic Jews could never really join the church. The precept that Talmudic Jews could never convert and become part of the church is heretical.
Peter was made by Paul to see that salvation had come to the Gentiles as surely as it had come to the Jewish disciples, not through obedience to the law but by grace through faith.
Salvation also came to those of Jewish heritage by grace and not through the law.
Because this contention is not recognised the argument is STILL raging in the church to this very day. You read on forums like this, folks determined to teach that we must obey the law to be saved. It is deadly doctrine.
The letter of the law killeth but the Spirit maketh ALIVE.
I agree.
This is just a brief overview of a very complex doctrine.
I agree with that too. It can take a long time to completely explore a doctrine, including misconceptions.