I think his point is that the gospel the 12 were preaching to Israel in Luke 9:6 was that Israel's promised King and Son of God is finally here in the flesh.
So the message in that gospel is "Change your minds, believe in Jesus as that promised Son of God, and you will have eternal life in his name (John 20:31)"
But now, none of us should be preaching that to unbelievers. And no, Paul was not preaching that gospel to the gentiles. That is not the gospel that saves today.
Instead, our gospel today is based on 1 Cor 15:1-4.
wow so what about this
it’s based on what Jesus the savior said it’s based upon . He then as I’ve shown said go teach all people of the world everything I taught you whoever believes and is baptized will be saved
Yet, they had no understanding of the gospel that Paul taught; the death, burial and resurrection of Jesus for sins.
Luke 18:
31 Then he took unto him the twelve, and said unto them, Behold, we go up to Jerusalem, and all things that are written by the prophets concerning the Son of man shall be accomplished.
32 For he shall be delivered unto the Gentiles, and shall be mocked, and spitefully entreated, and spitted on:
33 And they shall scourge him, and put him to death: and the third day he shall rise again.
34 And they understood none of these things: and this saying was hid from them, neither knew they the things which were spoken.
The gospel of the kingdom was for the Jews only. It included the promised restoration of Israel's kingdom.
“
The gospel of the kingdom was for the Jews only. It included the promised restoration of Israel's kingdom”
“Jesus saith unto them, Did ye never read in the scriptures, The stone which the builders rejected, the same is become the head of the corner: this is the Lord's doing, and it is marvellous in our eyes?
Therefore say I unto you, The kingdom of God shall be taken from you, and given to a nation bringing forth the fruits thereof.”
Matthew 21:42-
“And when they agreed not among themselves, they departed, after that Paul had spoken one word, Well spake the Holy Ghost by Esaias the prophet unto our fathers, Saying, Go unto this people, and say, Hearing ye shall hear, and shall not understand; and seeing ye shall see, and not perceive: For the heart of this people is waxed gross, and their ears are dull of hearing, and their eyes have they closed; lest they should see with their eyes, and hear with their ears, and understand with their heart, and should be converted, and I should heal them. Be it known therefore unto you, that the salvation of God is sent unto the Gentiles, and that they will hear it. And when he had said these words, the Jews departed, and had great reasoning among themselves. And Paul dwelt two whole years in his own hired house, and received all that came in unto him, Preaching the kingdom of God, and teaching those things which concern the Lord Jesus Christ, with all confidence, no man forbidding him.”
Acts 28:25-31 KJV
Israel rejected the kingdom it was sent to the world the same offer they had its the entire message of the New Testament those few who believed were sent out with the same offer to all people based on who would believe
another point the kingdom of God is not of this earth Israel will never be restored on this earth consider this is why we need salvation
“Behold, the Lord maketh the earth empty, and maketh it waste, and turneth it upside down, and scattereth abroad the inhabitants thereof.
The land shall be utterly emptied, and utterly spoiled: for the Lord hath spoken this word.
The earth also is defiled under the inhabitants thereof; because they have transgressed the laws, changed the ordinance, broken the everlasting covenant. Therefore hath the curse devoured the earth, and they that dwell therein are desolate: therefore the inhabitants of the earth are burned, and few men left.
Fear, and the pit, and the snare, are upon thee, O inhabitant of the earth.
The earth is utterly broken down, the earth is clean dissolved, the earth is moved exceedingly. The earth shall reel to and fro like a drunkard, and shall be removed like a cottage; and the transgression thereof shall be heavy upon it; and it shall fall, and not rise again.”
Isaiah 24:1, 3, 5-6, 17, 19-20 KJV
that’s what mans dominion under law led to its why we have now an offer of salvation everything flesh and physical is condemned even the earth so God sent the savior to offer entrance into his eternal kingdom which will appear when he returns to destroy this one
this is the Christian hope and this is the boundary of Gods promised kingdom within believers
“But
the heavens and the earth, which are now, by the same word are
kept in store, reserved unto fire against the day of judgment and perdition of ungodly men.
But the day of the Lord will come as a thief in the night; in the which the heavens shall pass away with a great noise, and the elements shall melt with fervent heat, the earth also and the works that are therein shall be burned up.
Nevertheless
we, according to his promise, look for new heavens and a new earth, wherein dwelleth righteousness.”
2 Peter 3:7, 10, 13 KJV
that’s Gods kingdom a new eternal
Perfect world ruled by Christ Jesus and filled with his children who accept his gospel