25In the LORD shall all the seed of Israel be justified, and shall glory.
And we know from Paul that those are Israel who are circumcised in heart--the children of the promise.
And one wouldn't bow to the Lord or confess his name unless one were circumcised in heart.
He is not one to force people to bow to him. They will bow because they recognize his glory and his righteousness, and that by the Holy Spirit.
Therefore, since all will bow, all Israel will be saved meaning all will be saved.
8 But what does it say? "The word is near you; it is in your mouth and in your heart,"[d] that is, the message concerning faith that we proclaim: 9 If you declare with your mouth, "Jesus is Lord," and believe in your heart that God raised him from the dead, you will be saved. 10 For it is with your heart that you believe and are justified, and it is with your mouth that you profess your faith and are saved. 11 As Scripture says, "Anyone who believes in him will never be put to shame."[e] 12 For there is no difference between Jew and Gentile—the same Lord is Lord of all and richly blesses all who call on him, 13 for, "Everyone who calls on the name of the Lord will be saved."[f]
16 But
not all the Israelites accepted the good news. For Isaiah says, "Lord, who has believed our message?"[h] 17 Consequently, faith comes from hearing the message, and the message is heard through the word about Christ. 18 But I ask: Did they not hear? Of course they did:
21 But concerning Israel he says,
"All day long I have held out my hands
to a disobedient and obstinate people."[l]
1 I ask then: Did God reject his people? By no means! I am an Israelite myself, a descendant of Abraham, from the tribe of Benjamin. 2
God did not reject his people, whom he foreknew
11 Again I ask: Did they stumble so as to fall beyond recovery? Not at all! Rather, because of their transgression, salvation has come to the Gentiles to make Israel envious. 12 But if their transgression means riches for the world, and their loss means riches for the Gentiles,
how much greater riches will their full inclusion bring! 13 I am talking to you Gentiles. Inasmuch as I am the apostle to the Gentiles, I take pride in my ministry 14 in the hope that I may somehow arouse my own people to envy and
save some of them.
Israelites not saved but yet is saved. From this complexity Paul writes we can conclude that overall God saves all people, but yet in the current time frame only a remnant get saved, and Paul is trying his best to save some of them.