Romans 9 and Romans 11 have different contexts. And Romans 11 has different contexts within itself.
Rom 11:7,
What then? Israel hath not obtained that which he seeketh for; but the election hath obtained it, and the rest were blinded
Here we see two different people:
- the election, the remnant, who have obtained salvation (by faith as you say)
- The rest who were blinded
The previous verses in the context have shown what will happen to the elect i.e. the remnant. They're saved. From 11:7 God tells what will happen to the rest, the ones who were blinded. That continues through the rest of chapter 11, including verse 26.
Rom 11:26,
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:
So now we see both the remnant and the rest of Israel saved. In other words, "
all Israel shall be saved"
I completely disagree that Romans 9 and Romans 11 have different contexts. I believe Romans 9-11 is all one narrative. Throughout Romans 9-11 Paul is making the case that being saved and being a child of God has nothing to do with one's nationality, but rather has to do with whether or not someone has faith, regardless of whether they are Jew or Gentile. And he shows throughout the Jew and Gentile believers were brought together as one. This can be clearly seen in all of these passages:
Romans 9:6 Not as though the word of God hath taken none effect. For
they are not all Israel, which are of Israel: 7
Neither, because they are the seed of Abraham, are they all children: but, In Isaac shall thy seed be called. 8
That is, They which are the children of the flesh, these are not the children of God: but the children of the promise are counted for the seed.
Romans 9:23 And
that he might make known the riches of his glory on the vessels of mercy, which he had afore prepared unto glory, 24 Even us, whom he hath called, not of the Jews only, but also of the Gentiles? 25 As he saith also in Osee, I will call them my people, which were not my people; and her beloved, which was not beloved. 26 And
it shall come to pass, that in the place where it was said unto them, Ye are not my people; there shall they be called the children of the living God.
Romans 10:9 That
if thou shalt confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised him from the dead, thou shalt be saved. 10 For with the heart man believeth unto righteousness; and with the mouth confession is made unto salvation. 11 For the scripture saith, Whosoever believeth on him shall not be ashamed. 12
For there is no difference between the Jew and the Greek: for the same Lord over all is rich unto all that call upon him.
Romans 11:17 And if some of the branches be broken off, and
thou, being a wild olive tree, wert grafted in among them, and with them partakest of the root and fatness of the olive tree; 18 Boast not against the branches. But if thou boast, thou bearest not the root, but the root thee. 19
Thou wilt say then, The branches were broken off, that I might be grafted in. 20 Well; because of unbelief they were broken off, and thou standest by faith. Be not highminded, but fear: 21 For if God spared not the natural branches, take heed lest he also spare not thee. 22 Behold therefore the goodness and severity of God: on them which fell, severity; but toward thee, goodness, if thou continue in his goodness: otherwise thou also shalt be cut off. 23 And
they also, if they abide not still in unbelief, shall be grafted in: for God is able to graft them in again. 24 For if thou wert cut out of the olive tree which is wild by nature, and wert grafted contrary to nature into a good olive tree: how much more shall these, which be the natural branches, be grafted into their own olive tree?
Romans 11:30 For as
ye in times past have not believed God, yet have now obtained mercy through their unbelief: 31 Even so have these also now not believed, that through your mercy they also may obtain mercy. 32 For God hath concluded them all in unbelief, that he might have mercy upon all.
What is the difference in the context between passages in Romans 9 like Romans 9:6-8 and Romans 9:23-26 and passages in Romans 11 like Romans 11:17-24 and Romans 11:30-32? None. The context is the same. In each Paul is saying that one's nationality is not what matters, but rather having faith is what matters. And in each he talks about the Gentiles being the children of God together with faithful Israelites.
Paul talks about 2 different Israels in Romans 9:6-8 and you can't ignore this when interpreting Romans 11:26.
Romans 9:6 Not as though the word of God hath taken none effect. For
they are not all Israel, which are of Israel: 7
Neither, because they are the seed of Abraham, are they all children: but, In Isaac shall thy seed be called. 8
That is, They which are the children of the flesh, these are not the children of God: but the children of the promise are counted for the seed.
In verses 7 and 8 here, Paul explains what he meant in verse 6. Verse 8 in particular makes it clear what he was saying in verse 6. By saying "they are not all Israel, which are of Israel" Paul was saying "they which are the children of the flesh, these are not the children of God". So, one Israel consists only of the children of God and the other Israel consists only of the children of the flesh. So, what Paul was saying in verse 6 then is they are not all Israel that is made up of the children of God (spiritual Israel), which are of Israel that is made up of the children of the flesh. To be part of the Israel that is made up of the children of God requires one to be a child of the promise since "the children of the promise are counted for the seed".
So, who are the children of the promise who are counted as the children of God and counted as being part of the Israel of which not all of national Israel (the children of the flesh) are part? That is the key to understanding which Israel it is of which all are saved.
Galatians 3:26 For
ye are all the children of God by faith in Christ Jesus. 27 For as many of you as have been baptized into Christ have put on Christ. 28
There is neither Jew nor Greek, there is neither bond nor free, there is neither male nor female: for
ye are all one in Christ Jesus.
29 And
if ye be Christ's, then are ye Abraham's seed, and heirs according to the promise.
There it is. The children of the promise are the children of God, which is not based on being children of the flesh, and they are those who have faith in Christ and belong to Him, whether Jew or Gentile. They are the ones who are part of the Israel of which all are saved. The spiritual Israel of God (Gal 6:15-16).