God's Purpose of Election
"When Rebekah had conceived children by one man, our forefather Isaac, though they were not yet born and had done nothing either good or bad—in order that God’s purpose of election might continue, not because of works but because of him who calls" (vv. 10–11).
Some first-century Jews were believers in Christ and thus saved, but not all of them. Lest anyone think that God's promise to redeem Israel had failed, Paul reminds us that the Lord never promised to save all those who can trace their physical ancestry back to the patriarchs. In fact, beginning with the first Jew—Abraham—God made a distinction between those who were merely children of the flesh and those who were children of the promise, and He saves only the latter (Rom. 9:6-8).
Who are the children of the promise, the true children of Abraham who will inherit all the covenant blessings promised to him (Gen. 12:1-3; 15; 17:1-8; 22:15-18)? Paul tells us in Galatians 3 that these children are those who trust only in Christ for salvation. But why do the children of the promise rest in Christ alone for their righteousness? The Apostle gets into that in today's passage.
Continuing his case that the Lord never promised to save all ethnic Israelites, Paul turns to the patriarch Isaac's family and points specifically to God's choice of Jacob over Esau (Rom. 9:10-13). This strengthens the Apostle's argument masterfully. Though God's selection of Isaac over Ishmael shows that the true children of Abraham—the heirs of salvation—are reckoned not by physical descent but by promise, those who disagreed with Paul could point out that Isaac and Ishmael had different mothers and infer that having the promised line come through Isaac meant God pledged to save every ethnic Jew. After all, Isaac's father (Abraham) and mother (Sarah) were Jewish, but Ishmael's mother (Hagar) was not. This could not be done with Jacob and Esau. The Apostle notes specifically that these brothers had the same Jewish mother, Rebekah, as well as the same Jewish father, Isaac (v. 10). God's choice to save Jacob had nothing to do with his parentage or with Jacob himself.
Paul emphasizes this point as he notes that the Lord's choice of Jacob over Esau occurred before they were born and before they could do anything good or bad (vv. 11-13). When God decided to save Jacob, there was nothing that Jacob had done that motivated his being chosen. No existing merit—for Jacob did not yet exist—and not even any foreseen merit. We are told that the Lord made His choice simply so that His purpose of election would continue, and not because Jacob was more lovable than Esau, more righteous than Esau, or even because God knew that Jacob would choose Him when given the chance.
Coram Deo
John Calvin comments on today's passage that "the Lord in his gratuitous election is free and exempt from the necessity of imparting equally the same grace to all; but, on the contrary, he passes by whom he wills, and whom he wills he chooses." God chooses people for salvation according to His good pleasure and not because of anything in them. In fact, He chooses to save sinners in spite of their sin. We should be eternally grateful that He does this; otherwise, no one could be saved.