What you wrote is true regarding salvation, but God is bigger than that. Salvation is the key teaching in the Bible, but He did many things for Israel that are not directly related. He even intervened in Babylon and Persia for Israel. Matthew 10:29-31: Sparrows are not part of the plan for salvation, but God cares for them. God does many things that are for His glory, and picking a favorite nation is one of them. God has a plan for each one of us when Jesus comes back. Why can't He have a special plan for believing Jews?
He could, but Scripture says there is one olive tree with both natural branches and wild branches grafted on. Scripture says that Jews and Gentiles are, in the Messiah, a single people. Scripture says that all who are in Christ are heirs with Christ.
Scripture also says that Israel was chosen because it's about Jesus. God doesn't have two plans, two peoples, two gospels. There is one story of Redemption. One people of God in the Messiah. One Gospel for the whole world that runs from Genesis onward and is for everyone.
Salvation is not just about what happens after we die, salvation is the entirety of God's rescue project for all of creation.
This gets to the heart of what's happening, meta-level, in the entire Bible. This gets to the heart of what the Gospel even is. This gets right to the heart of everything that's ever happened, is happening, and will happen; from Creation to Eschaton, and World Everlasting.
It's that everything was broken through Adam. And Adam's progeny bear his brokenness, and indeed, the whole of creation bears the wounds of that sin; for human beings were given the great gift of having dominion over creation, to rule over creation with wisdom, love, peace, as the Image of God--as kings and priests; and that was fumbled, massively. And now everything is broken. That brokenness is repeatedly seen, as we watch Cain murder Abel. As we watch the world become hideous through sin, so God sends a great flood, preserving Noah, his family, and representatives of all the animals. We watch and see man, again, grow arrogant, building a tower to claim heaven, and God breaks their efforts by confusing the languages.
And then God calls an old man and his wife, Abram and Sarai, who will become Abraham and Sarah. He says to them that they would bear a child even at his advanced age, and his wife's barren state--and He keeps that promise. Abraham sired Isaac, and Isaac sired Jacob, and Jacob sired the twelve patriarchs. Then they went into Egypt, where the whole Hebrew people were enslaved. God redeems the nation, taking them from Egypt, gives them the Law and Covenant, and brings them into the land of promise.
The people enter the land and are ruled by their chieftans/judges, but they grow jealous of the nations and desire a king, even though they already have a King, they are ruled by King YHWH, God. So God gives them a king, and he's not very good, but He says He'll give them a different king, and through this shepherd-king will come the King of kings. David's son Solomon then rules, and though wise, and allowed to make a permanent Tabernacle, the Temple in Jerusalem, is nevertheless a man of many problems. After Solomon the nation is divided, north and south. Prophet after prophet comes, warning, pleading, and promising--the word of God comes over and over to warn and to heal. But the north is taken out by Assyria. And then later the south is taken out by Babylon. But in Babylon God continues to remind them of the promises. He will restore them to the land, the Temple will be rebuilt. Though they would no longer be ruled by a king, nevertheless the King of David's line is still come.
They are brought back into the land under the Persians. The Temple is rebuilt along with the city of Jerusalem. But Persia will be conquered by the Macedonians. And the Macedonians will fracture into competing Greek kingdoms. A short-lived independence through the Maccabees occurs; but sets the stage for fractured problems, the Romans then come, and then Jesus is born--the Son of David, the King of kings, the Messiah.
What then begins to unfold is all the fulfillment of what was said, that the Messiah must suffer and then after three days rise again. And so Jesus is betrayed, arrested, and handed over the Gentile rulers--Pilate. He is sentenced to death by crucifixion, and is beaten and mocked and nailed to a cross. And there He bears not only all the shame of Israel, but of the whole world. And He dies. On the third day He rises, defeating death, conquering hell, crushing the devil under His foot--just as promised right there in the Garden so long ago. After forty days He ascends, to take His seat as the enthroned Messiah, for the Son of Man is brought before the Ancient of Days and given everlasting kingdom and dominion, as Daniel had seen in his vision. The enthroned Christ, the Son of David on His throne, rules and reigns with all authority, with kingdom everlasting, over all things. And as He promised, the Holy Spirit was sent and poured out, and see here how the curse of Babel is reversed. For when men sought to ascend to heaven their languages were confused and they were scattered to all the corners of the earth to become the nations; here the Holy Spirit comes down from heaven, and unites the nations through an understanding of languages, that the Gospel might go forth from Jerusalem to the whole world, that all nations should be made disciples, being baptized in the name of the Father, Son, and the Holy Spirit, and learn the way of Messiah Jesus. For so long ago, too was it promised, that the Gentiles would come to Mt. Zion to worship. And so, now, they shall--for out of Zion comes the Gospel, and to Mt. Zion, the true Zion which is Jesus Christ, come the nations to worship the one true God, and partake of the true sacrifice of His flesh and blood.
See, now, too the promises in the Messiah. For where Adam broke, Christ has healed. Where children murdered, in Christ children are united in peace. Where the nations were broken and scattered, in Christ they are brought together and united together. For what God began through Abraham, and the reason He chose the nation of HIs choosing, was to be a blessing to all nations, and that Abraham should become the father of not just a great nation, but of all nations--through the Messiah. For the Messiah is the Seed of Abraham. So Jew and Gentile, without distinction, are brought together in the Messiah. Elder brothers and younger brothers all alike; and it matters not at what hour of the day the laborers were hired to work the vineyard, all receive the same wage as the Lord Himself has taught us. And now we look forward, to that future day, when Christ returns, to judge the living and the dead. For on that Day the dead shall rise, this mortal shall be made immortal; this corruptible flesh made incorruptible. What is sown soulish is raised Spiritual; what is sown in dishonor is raised in honor. We have born the flesh of Adam, we shall bear the flesh of the Risen Son of God. On that Day, He shall judge. On that Day He will have those on His right and on His left. And when this time comes, God will make all things new, for there shall be new heavens, new earth--the creation itself which from the time of Adam until now has cried out in labor pains longing in the hope of redemption and renewal that is coming shall at long last be freed from its futility of death, and all things shall be made new.
For Adam broke, and Christ heals.
Through the whole Bible this drama is unfolding, it is pushing forward, rushing headlong to Christ. And in Christ all is summed up together, and God, according to His Covenant Faithfulness to His creation shall set all things to rights.
Israel was chosen, for through her would come Christ.
Because Israel was the vehicle of the covenants and the promises and the patriarchs and the prophets; all toward Christ.
And that is not nothing, St. Paul says that is a most excellent thing. But though they have been at the vineyard since daybreak, and we who are Gentiles are now coming at the later hour does not mean ours is a separate wage, a lesser wage, a higher wage, or a different wage. For of two peoples, there is one people. For here, in the Messiah, the Gentile is brought into the commonwealth of Israel, no longer a stranger. That's Scripture, explicit and plain.
If God has some different plan for Jewish Christians than He does for Gentile Christians, then at best God has not seen fit to tell us what it is, for Scripture knows nothing of it. But at worst, it means we cannot trust Scripture, for Scripture speaks of the one unified plan for all in the Messiah.
-CryptoLutheran