In chapter 10 of Isaiah, the prophet declares: “A remnant will return, the remnant of Jacob, to the mighty God” (v.21). This was in the first place a promise that the Lord would return at least some of his people to the Promised Land after their time of exile in a foreign country (perhaps Assyria, or Babylon).
But more than a promise of a physical homecoming, these words refer to the spiritual return of the people of God to their Lord. Most fundamentally, it is a promise of salvation from sin and death. With that in view, there are two ways we can read this promise.
First, we can emphasize the word “remnant”: “A remnant will return… to the Mighty God.” To read it this way highlights the truth that out of the multitudes who were outwardly identified as the people of God, only some will be saved. This is how Isaiah himself, in the next verse, explains the promise: “For though your people Israel be as the sand of the sea, only a remnant of them will return. Destruction is decreed, overflowing with righteousness” (v.22).
And this is how the apostle Paul applies this verse in his letter to the Romans. He explains that although the vast majority of his fellow Jews rejected Jesus as the Christ, and so were lost in their sin and unbelief, the promises of God for Israel still stood. That’s because the promise of God for the salvation of Israel applied not to every physical descendent of Abraham, but to those whom Paul calls the “children of the promise” (Romans 9:8). It is they, the remnant, who will be saved by faith in Christ: “And Isaiah cries out concerning Israel: “Though the number of the sons of Israel be as the sand of the sea, only a remnant of them will be saved” (v. 27).
Later in chapter 11, Paul calls this remnant “… a remnant, chosen by grace” (v.5). So the remnant is God’s elect of Israel, those descendants of Abraham whom the Lord graciously chose in eternity to inherit salvation. And although Paul is referring to the elect among the Jews, we can expand the remnant to include all of God’s elect, both Jew and Gentile. In Christ, we are the remnant who will – by God’s sovereign grace – receive mercy and deliverance on the Day of Judgment.
In light of that, we can read the Lord’s promise in Isaiah another way. That is, we can emphasize the word “will”: “A remnant will return, the remnant of Jacob, to the mighty God.” The promise is that, in Christ, God will guard and keep us in his love until the day of the return of our Savior.
And with that promise we need not fear anything in this life that might threaten to separate us from God’s love to us in Christ. God has set us apart in his Son, and though Satan, the world, and our own flesh conspire to snatch us out of the hands of our Savior, we are kept safe in his loving care. No matter how treacherous the path we walk in this world, as we follow Christ, he will lead us to our eternal home.
Soli Deo Gloria!