The elect in that verse is obviously not Christians because they had not yet obtains salvation in Christ Jesus.
Paul is talking about the Jews, Israel. When Paul refers to them of other nations, he uses the term Gentiles.
Once again, you are attempting to make the Two Peoples of God doctrine work by ignoring the facts.
Paul addressed the crowd as "all the house of Israel" on the Day of Pentecost when about 3,000 Israelites accepted the New Covenant promised in Jeremiah 31:31-34.
Act 2:36 Therefore
let all the house of Israel know assuredly, that God hath made that same Jesus, whom ye have crucified, both Lord and Christ.
Paul reveals two different groups of Israelites in Romans 11.
There was a "remnant" which remained faithful to God, and the others were like the Baal worshippers who turned from God's plan.
Rom 11:1 I say then, Hath God cast away his people? God forbid.
For I also am an Israelite, of the seed of Abraham, of the tribe of Benjamin.
Rom 11:2 God hath not cast away his people which he foreknew. Wot ye not what the scripture saith of Elias? how he maketh intercession to God against Israel, saying,
Rom 11:3 Lord, they have killed thy prophets, and digged down thine altars; and I am left alone, and they seek my life.
Rom 11:4 But what saith the answer of God unto him? I have reserved to myself seven thousand men, who have not bowed the knee to the image of Baal.
Rom 11:5
Even so then at this present time also there is a remnant according to the election of grace.
Hebrews chapter 11 reveals all of the Old Testament Saints were saved through faith in the Messiah that was to come, as God had preached to Abraham.
There is only one people of God in John 10:16.
Therefore, all attempts to separate faithful Israel from the Church are doomed to failure.
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