Jews, who are they?

The total number of people who hold or are eligible for Israeli citizenship under the "Law of Return"— defined as anyone with at least one Jewish grandparent, and who does not profess any other religion — is estimated at around 23 million, of which 6.6 million were living in Israel as of 2015. Figures for these expanded categories are less precise than for the core Jewish population.

While dozens of countries host at least a small Jewish population, the community is concentrated in a handful: Israel and the United States account for 83% of the Jewish population, while a total of 98 countries host the other 17%.

The term "Ashkenazi" refers to Jewish settlers who established communities along the Rhine River in Western Germany and in Northern France dating back to the Middle Ages.  Once there, they adapted traditions from Babylon, The Land of Israel, and the Western Mediterranean to their new environment.

The Holocaust had a devastating impact on the Ashkenazim, affecting almost every Jewish family. It is estimated that in the 11th century Ashkenazi Jews composed only three percent of the world's total Jewish population, while an estimate made in 1930 (near the population's peak) had them as 92 percent of the world's Jews. Immediately prior to the Holocaust, the number of Jews in the world stood at approximately 16.7 million.  Statistical figures vary for the contemporary demography of Ashkenazi Jews, ranging from 10 million to 11.2 million. Sergio Della Pergola in a rough calculation of Sephardic and Mizrahi Jews, implies that Ashkenazi Jews make up less than 74% of Jews worldwide. Other estimates place Ashkenazi Jews as making up about 75% of Jews worldwide.

Those who call themselves Jews today do so because of ancestry and probably a cultural or religious connection or belief.  They must want to maintain that identity to some extent. 

Romans 11.26 speaks of all Israel being saved.  Though the Apostle Paul says in Romans 9 that they are not all Israel who are of Israel, the reference to Israel concerns their national identity. 

This salvation in Romans 11.26 is as a people, a nation.  It does not mean every individual Jew will be saved—spiritually, as in being right with God, and physically, as an identifiable legitimate nation among nations in a geographically fixed place.

It seems a little complicated in what Paul is saying in Romans 11.  Paul speaks about the breaking off of some of the natural branches (Jews/ Israelites), in the analogy of an olive tree and its branches, being meant as the setting aside of the Jewish nation, but not the elimination of them as individuals Jews from being saved—since believing Jews in Christ become part of the Church.  Paul speaks of them being grafting in "again" in vs 23 which must speak of something other than individuals, for individuals can be saved through the present age of the Church.  This must look to them as a people, nation.  The word "again" is not suggesting that certain individuals were broken off, and then grafted in again when they believed again.  The unnatural branches, being non-Jews, gentiles, that were grafted in could be "cut off" if they don’t continue in belief, 11.22—even here the view must be to a people as in the gentiles (the unnatural branches in the analogy).  The issue here must be a place of privilege and blessing, represented in the Olive tree.  The people, nation of Israel will be grafted in again to this place of privilege and blessing.

Charles Hodge on Romans 11:26:  "Israel here must mean the Jewish people, and 'all Israel' the whole nation.  The Jews, as a people, are now rejected; as a people they are to be restored.  As their rejection, although national, did not include the rejection of every individual, so their restoration though national, need not include the salvation of every Jew.  All Israel does not mean all the true people of God, as Augustine, Calvin, and others explain it; nor all the elect Jews -- i.e., all that part of the nation which constitute "the remnant according to the election of grace" --but the whole nation, as a nation. (Romans Commentary

Who is Israel?  They are both ethnic and spiritual.  The ethnic determination is that one grandparent being Jewish-- and a religious one--of Jewish belief.  The "law of Return is a matter of debate, since most peoples are not ethnically pure.  There must be some genetic link.  Israel has a genetic requirement."

The Abrahamic Covenant was a promise of blessing through Abraham to all nations, and a promise of blessing to his natural descendants in a land of promise. Gen 13.14-15 "And the Lord said to Abram, after Lot had separated from him: “Lift your eyes now and look from the place where you are—northward, southward, eastward, and westward; for all the land which you see I give to you and your descendants forever."

Those descendants were placed under covenant that required obedience to be blessed in the land of promise, being the Mosaic.  But they failed.  And so were driven out.

But because of the Abrahamic Covenant, God made a new covenant, so a natural seed who count as spiritual seed may inherit the promises.

The Jews are saved in same manner as Gentiles.  Acts 15.11

The new covenant guarantees the continuance of the nation.  Jeremiah 31.31-37

Genesis 15.7-21: Abraham is given a  promise of the land. 

Deut 4.26-32:  Moses foretold Israel's failure and judgment, but because of the covenant with the father's, Israel will be restored.

Romans 11: 23-29  says they will be grafted in again if they don’t continue in unbelief.

Only those who count as spiritual seed inherit the promises:  Romans 9-11.  It will be natural seed that count as spiritual seed.  This is with reference to certain temporal promises.

God will both save and bless his people.  Those people are of differing identities in time, but that salvation and blessing is through the one who came riding on a donkey, and is coming again, whose authority is from "sea to sea." Zechariah 9.9-10

In Zech 5, we see an angel pushing "wickedness" back down into the basket, and putting a lid on it.  Could this compare to 2 These 2 concerning the restraining of the revealing of the son of lawlessness?  Daniel 10:12 reveals an angelic conflict involving restraining.

A house prepared for it--could this be the temple for the “Abomination Of Desolation?”

Yet the restraining of 2 Thess 2 seems an issue of timing and circumstances.  It involves the right time and circumstances for that particular roll of the “lawless one” as described.

The plan of God concerning Israel was not restoration following Pentecost.  God could have done it with the few thousands that did respond to the Gospel, but he didn't.  Romans 11 explains kind of why. "But through their fall, to provoke them to jealousy, salvation has come to the Gentiles. Now if their fall is riches for the world, and their failure riches for the Gentiles, how much more their fullness!"

If a larger number would have believed, how would prophecy had been fulfilled?  Would the temple had been destroyed still, as Jesus foretold?  Wouldn’t it need to be destroyed, since that was judgment on the nation: "they will not leave in you one stone upon another, because you did not know the time of your visitation.” Luke 19:44

How would the abomination of desolation fit in and the great tribulation period? 

I'm sure there is a creative way to explain this.  But their rejection and God's plan is all figured in.  Things had to take their course; there has to be an offer of the kingdom so it can be rejected--even though the rejection was to be inevitable.

Again, God could have restored Israel with the remnant who believed, but that was not God's plan, for Romans 11 reveals that plan.

The Church practices baptism and communion.  One could argue the Jews were to practice these until Christ came, during that period between Pentecost and second coming. 

Mat 24.18 "All these are but the beginning of the birth pains."  Birth pains are the sorrows and difficulty that precede a birth.  This was true for Israel coming out of Egypt.  It will be true for Israel coming out of Great Tribulation.  It is true for creation in Romans 8.22 "For we know that the whole creation groans and labors with birth pangs together until now."