“I say then, has God cast away His people? Certainly not! For I also am an Israelite, of the seed of Abraham, of the tribe of Benjamin. God has not cast away His people whom He foreknew.”
When Paul asks this question in Romans 11:1-2, he has the Book of Lamentations specifically in mind:
“For the Lord will not cast off forever.
Though He causes grief,
Yet He will show compassion
According to the multitude of His mercies” (Lam. 3:31-32).
In Lamentations, the author is mourning over the destruction of Jerusalem in 586 BC, which he recognizes as deserved due to Judah and Israel’s repeated apostasy from Yahweh throughout the period of the Old Covenant, which continued up until the destruction of Jerusalem in 70 A.D. And yet even in the midst of this, he has hope in the nation’s forgiveness and restoration, in whatever form that may take.
It’s this question of form that Paul is addressing in Romans 9-11. Paul makes it clear that not every last Israelite will be saved, indicated by his repeated reference to “a remnant“ (9:27, 11:5). Both the discussion of election in Romans 9 and 11 (some are chosen, others are not), as well as Paul’s illustration of olive branches cut out and some grafted back in, demonstrate that he recognizes that only certain Israelite individuals will be saved. “For many are called, but few are chosen” (Matthew 22:14). And this election, as he shows us, is of grace, not of works (Rom. 11:5-6). If it is of grace for the Israelites, how much more is it of grace to the Gentiles, who were not the beneficiaries of God’s grace to begin with (Rom. 11:11-24; Eph. 2)?
The result, then, of Israel’s apostasy and return to Yahweh, is not a nation of Israel restored to its Old Covenant position in the end times, but an Israel, an ekklesia, of which Gentiles are as much a part as the physical sons of Abraham, from the first century into eternity (Isaiah 60).
Paul does not see the fact of election by grace to be in contradiction with the notion of apostasy, but rather a complementary truth. The discussion of election in Romans 9 itself contains within it the idea that some who, in one sense, are of the people of God, may not in another sense actually be of the people of God. The difference between the two groups according to the action of God depends upon His mercy and grace, Paul tells us. But here in Romans, as elsewhere in Scripture, Paul makes it clear that from the perspective of the individual man, continuance in salvation depends on his perseverance in both faith and obedience. Good works are essential to final salvation. Not only does he make this clear in Rom. 11:16-24, but it is emphasized throughout the book (2:5-29; 8:1-17). The mercy and grace that makes a man justified by faith puts him in such a state that while he may occasionally sin, sin does not dominate him. He becomes a man who reckons himself dead to sin through the finished work of Christ, and being in union with Christ through His death and resurrection, does not yield himself up to sin as its slave (Rom. 6).
The key question to it all is this - who does the saving? And Paul makes it clear that it is God, through election, through predestination, through calling, through justification, through perseverance, and through glorification (8:28-30). The warnings must be heeded. But the man who God has determined to save will heed those warnings and persevere until the end of his life.
And so perseverance in faith, a perseverance that Old Covenant Israel failed in, is required for final salvation. But the faith that is required is not a faith in one’s own works or obedience, but rather faith in the the One who promises to keep ahold of the man who trusts in Him, the kind of trust that perseveres in obedience.