When Apostle Paul made reference to the Jews in the NT, he meant those who were under the Law of Moses, These were the descendants of Abraham, Isaac and Jacob who had been set free from the bondage of Egypt.
The Apostle went to great length in detail to explain that it is not the lineage of Abraham that counts for salvation but rather Abrahams promise given him through faith which was fulfilled by Christ, Abraham's only seed and heir of the promise given Him by God. That through Christ He (Abraham) would be the father of many Nations..
(It is in that Light and in the fulfilment of that promise which "The Israel of God" is to be found)..
Grace has made obsolete Race or Nationality (Jew or Gentile) for that matter.. It is all about being a 'New Creation' in Christ Jesus.. "Old things have passed away"....
A Jew just as a Gentile (other nationalities) must be grafted into the Olive Tree. which is (a symbolic representation of The Israel of God).
Let us understand; that this "Olive Tree" is not the Present Zionist State of Israel!
in other words, the 'Zionist state' is not the Symbolic Olive Tree about which Apostle wrote
Apostle said; "and SO all Israel will be saved" He is not referring to the present Zionist state but only to those grafted in by the Grace of God (Jews & gentiles) They both together form the Israel of God which is to be save in its completeness..
There is no future promise to any man, Jew or Gentile outside the ordained manner of Abraham's Faith..
The words 'and SO' defines the fashion/way by which The Israel of God is to be saved and that is "By Grace through Faith" Just as Apostle preached...
So; Abraham was called out/taken from a Gentile Nation (Ur) Gen 11: 31 to become the father of many Nations, Israel included...
As can be seen in the symbolic "Olive Tree" The Israel of God consists of both groups Jews and Gentiles who all have their source in Abraham. as the father of faith.....
Prior to His ascension into heaven, Jesus the Seed of the promise given to Abraham, commissions the disciples to Go and make disciples of all Nations..
What a marvellous Plan of redemption is entailed in the Grace of God..