romans 11:23 And they also, if they abide not still in unbelief, shall be graffed in: for God is able to graff them in again. - Free Bible Online

      23. And they also--"Yea, and they"
      if they abide not still in unbelief, shall be grafted in: for God is able to graft them in again--This appeal to the power of God to effect the recovery of His ancient people implies the vast difficulty of it--which all who have ever labored for the conversion of the Jews are made depressingly to feel. That intelligent expositors should think that this was meant of individual Jews, reintroduced from time to time into the family of God on their believing on the Lord Jesus, is surprising; and yet those who deny the national recovery of Israel must and do so interpret the apostle. But this is to confound the two things which the apostle carefully distinguishes. Individual Jews have been at all times admissible, and have been admitted, to the Church through the gate of faith in the Lord Jesus. This is the "remnant, even at this present time, according to the election of grace," of which the apostle, in the first part of the chapter, had cited himself as one. But here he manifestly speaks of something not then existing, but to be looked forward to as a great future event in the economy of God, the reingrafting of the nation as such, when they "abide not in unbelief." And though this is here spoken of merely as a supposition (if their unbelief shall cease)--in order to set it over against the other supposition, of what will happen to the Gentiles if they shall not abide in the faith--the supposition is turned into an explicit prediction in the verses following.

JFB.