The Promise of all Israel shall be saved as Per Isa 45:17
17 But Israel shall be saved in the Lord with an everlasting salvation: ye shall not be ashamed nor confounded world without end.
Rom 11:25-26
25 For I would not, brethren, that ye should be ignorant of this mystery, lest ye should be wise in your own conceits; that blindness in part is happened to Israel, until the fulness of the Gentiles be come in.
26 And so all Israel shall be saved: as it is written, There shall come out of Sion the Deliverer, and shall turn away ungodliness from Jacob:
This is fulfilled by all who are Justified by Faith, whether jew or Gentile, thats the Gospel promise to Abraham Gal 3:8-9
8 And the scripture, foreseeing that God would justify the heathen through faith, preached before the gospel unto Abraham, saying, In thee shall all nations be blessed.
9 So then they which be of faith are blessed with faithful Abraham.
Thats the seed of Israel promised to be Justified in the Lord Isa 45:25
25 In the Lord shall all the seed of Israel be justified, and shall glory.