26 And in this way all Israel will be saved, as it is written,
“The Deliverer will come from Zion,
he will banish ungodliness from Jacob”;
27
“and this will be my covenant with them
when I take away their sins.”
This is how they will ALL be saved by the new covenant that forgives sins.
Has Jesus established the new covenant?
Romans 11:7 What then? Israel hath not obtained that which he seeketh for; but the election hath obtained it, and the rest were blinded.
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.
When?
More on that in a sec...
But first, the fact that God IS able to graft them in again....
11:24 For if thou wert cut out of the olive tree which is wild by nature, and wert graffed contrary to nature into a good olive tree: how much more shall these, which be the natural branches, be graffed into their own olive tree?
Now, back to this WHEN issue...despite His having concluded the rest blind...
11:25 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. 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: 11:27 For this is my covenant unto them, when I shall take away their sins.
"Blindness" (a hardening) "in part (that is to say, temporarily) is happened to Israel..."
How long?
"...until the fullness of the Gentiles be come in."
Next verse - "And so all Israel shall be saved.
...as it is written..."
When?
At His return...
Acts 3:19 Repent ye therefore, and be converted, that your sins may be blotted out, when the times of refreshing shall come from the presence of the Lord; 3:20 And he shall send Jesus Christ, which before was preached unto you:
Verse 20 is not conditioned on verse 19. Rather, verse 19 depends on verse 20.
Note the next passage...
3:21 Whom the heaven must receive until the times of restitution of all things, which God hath spoken by the mouth of all his holy prophets since the world began.
Which is what this is...
Romans 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: 11:27 For this is my covenant unto them, when I shall take away their sins.
When will He take away their sins?
Acts 3:19 Repent ye therefore, and be converted, that your sins may be blotted out, when the times of refreshing shall come from the presence of the Lord; 3:20 And he shall send Jesus Christ, which before was preached unto you:
When the times of refreshing shall come from the presence of the Lord.
In other words, when the Father shall send back Jesus Christ, which before was preached unto them.
3:22 For Moses truly said unto the fathers, A prophet shall the Lord your God raise up unto you of your brethren, like unto me; him shall ye hear in all things whatsoever he shall say unto you. 3:23 And it shall come to pass, that every soul, which will not hear that prophet, shall be destroyed from among the people.
That destruction happens when He returns.
Which is this...
Isaiah 59:18 According to their deeds, accordingly he will repay, fury to his adversaries, recompence to his enemies; to the islands he will repay recompence. 59:19 So shall they fear the name of the LORD from the west, and his glory from the rising of the sun. When the enemy shall come in like a flood, the Spirit of the LORD shall lift up a standard against him. 59:20 And the Redeemer shall come to Zion, and unto them that turn from transgression in Jacob, saith the LORD. 59:21 As for me, this is my covenant with them, saith the LORD; My spirit that is upon thee, and my words which I have put in thy mouth, shall not depart out of thy mouth, nor out of the mouth of thy seed, nor out of the mouth of thy seed's seed, saith the LORD, from henceforth and for ever.
Which is why Paul ends that part of Romans with...
Romans 11:27 For this is my covenant unto them, when I shall take away their sins. 11:28 As concerning the gospel, they are enemies for your sakes: but as touching the election, they are beloved for the fathers' sakes. 11:29 For the gifts and calling of God are without repentance.
At the same time that he once more mentions there that an interruption of that has taken place and that God is now doing something else during said interruption.
Just as he had reminded them of that in Romans 9's "What if God willing to shew forth His wrath...endured..."
He then says something more about this interruption, and what God was now doing during said interruption...
Romans 11:30 For as ye in times past have not believed God, yet have now obtained mercy through their unbelief: 11:31 Even so have these also now not believed, that through your mercy they also may obtain mercy. 11:32 For God hath concluded them all in unbelief, that he might have mercy upon all.
Paul's point being that even though God was now not dealing with Israel as a nation, nor per His Covenants with them, He had not left them out in the cold during His interruption of that.
Both issues are still in God's mind...
Romans 11:13 For I speak to you Gentiles, inasmuch as I am the apostle of the Gentiles, I magnify mine office: 11:14 If by any means I may provoke to emulation them which are my flesh, and might save some of them. 11:15 For if the casting away of them be the reconciling of the world, what shall the receiving of them be, but life from the dead?
As Paul reminds the Romans in chapter 15; the Romans knew these things.
Thus, Paul's writing to them is more a further elaborating on some of those things and reminder of them to the Romans. He writes as if he had expected that they knew these things and would thus be able to fill in all the gaps we have to search out in Scripture.
Keep that in mind about Paul's writings - they are often reminders of things his readers had already been taught.
Even his "Behold I shew you a mystery" in 1 Cor. 15, is not new. It is a reminder to the Corinthians of what he and or his fellow laborers had already taught them.
Acts 17: 11, 12.
Rom. 5:6-8.