Not all Israel is Israel; nor are all descendants of Abraham Israel.
Flesh vs Spirit
Two Jerusalems: one above that is of God;
the other below that is not; yet persecutes those of the promise/Spirit, the true followers of Jesus.



 22For it is written, that Abraham had two sons, the one by a bondmaid, the other by a freewoman.

23But he who was of the bondwoman was born after the flesh; but he of the freewoman was by promise. 24Which things are an allegory: for these are the two covenants; the one from the mount Sinai, which gendereth to bondage, which is Agar.

25For this Agar is mount Sinai in Arabia, and answereth to Jerusalem which now is, and is in bondage with her children. 26But Jerusalem which is above is free, which is the mother of us all.

27For it is written, Rejoice, thou barren that bearest not; break forth and cry, thou that travailest not: for the desolate hath many more children than she which hath an husband.

28Now we, brethren, as Isaac was, are the children of promise.

29But as then he that was born after the flesh persecuted him that was born after the Spirit, even soit is now.

30Nevertheless what saith the scripture? Cast out the bondwoman and her son: for the son of the bondwoman shall not be heir with the son of the freewoman.

31So then, brethren, we are not children of the bondwoman, but of the free.
Galatians 4:22-31

and

6But [it is] not as though the word of God has failed. For they are not all Israel who are [descended] from Israel;

7nor are they all children because they are Abraham's descendants, but: "THROUGH ISAAC YOUR DESCENDANTS WILL BE NAMED."

8That is, it is not the children of the flesh who are children of God, but the children of the promise are regarded as descendants.
Romans 9:6-8