But it is not as though the word of God has failed. For they are not all Israel who are descended from Israel; nor are they all children because they are Abraham’s descendants, but: ‘Through Isaac your descendants will be named.’ That is, it is not the children of the flesh who are children of God, but the children of the promise are regarded as descendants.
One Arminian states: “Arminians come to a different conclusion about Romans 9. We hold that it’s about the election of the nation Israel to serve God’s greater purposes.”
However, I cannot say that I’m in agreement with that assessment.
First of all, Romans 9:1-3 is what is motivating Paul, and what is deeply personal to him, and is somewhat reiterated at Romans 10:1.
Secondly, Romans chapter 9 is a continuation of Paul’s evangelical appeal to the unbelieving Jew, in which chapter 9 takes a different approach, by now focusing on refuting false Jewish Assurance, which has otherwise stood as a blockade from conversion to Christ.
The mistaken Jewish perspective was that yes, all are Israel, who are physically decended from Israel, and yes, the children of God are those who are Abraham’s descendants.
John the Baptist states at Matthew 3:9: “Do not suppose that you can say to yourselves, ‘We have Abraham for our father’; for I say to you that from these stones God is able to raise up children to Abraham.”
Paul presents the issue of Jewish False Assurance at v.7, and then builds into the climax of the refutation at v.13. So v.13 refutes the errant premise of v.7. For if one was assured of unconditional salvation by virtue of being a son of Abraham, then wouldn’t it also have to be admitted that Esau/Edom would have the same assurance, by also being sons of Abraham?, and yet, look at what God said about Esau/Edom, and hence the false premise of v.7 is defeated by the biblical fact of v.13.
The rest of the chapter reflects on the fact that Jewish unbelief was a factor of a forewarned hardening, namely, their hardening, and which seems to borrow from the Potter imagery of Jeremiah 18:1-13.