That was not how the "earlier church" (200 ad - 400 ad) saw it. James, the epistles of Peter and John, Hebrews, and Jude were not addressed to the gentile church, but to the Jewish believers. Indeed, texts found from the Sect of the Nazoreans place those letters between Acts and Romans.
Well then Romans applies this same term to Gentiles --
ok so 'Israel' as spiritual Israel - even in Romans 11 - because salvation is never "by nations" in the gospel - it is always "individual by individual"
we are all grafted in as Israel - we have texts for that -
Romans 2
26 Therefore, if an
uncircumcised man keeps the righteous requirements of the law, will not his uncircumcision be counted as circumcision? 27 And will not the physically uncircumcised, if he fulfills the law, judge you who,
even with
your written
code and circumcision,
are a transgressor of the law? 28 For
he is not a Jew who is one outwardly, nor is circumcision that which is outward in the flesh; 29 but
he is a Jew who
is one inwardly; and circumcision
is that of the heart, in the Spirit, not in the letter; whose praise
is not from men but from God.
Romans 9
6 But it is not that the word of God has taken no effect. For
they are not all Israel who are of Israel, 7
nor are they all children because they are the seed of Abraham; but, “In Isaac your seed shall be called.” 8 That is, those who
are the children of the flesh, these
are not the children of God; but
the children of the promise are counted as the seed. 9 For this
is the word of promise: “At this time I will come and Sarah shall have a son.”
1 Cor 7
17 Only, as the Lord has assigned to each one, as God has called each, in this manner let him walk. And so I direct in all the churches. 18 Was any man called
when he was already circumcised? He is not to become uncircumcised. Has anyone been called in uncircumcision?
He is not to be circumcised. 19
Circumcision is nothing, and uncircumcision is nothing, but
what matters is the keeping of the commandments of God
Romans 11
11 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. 2 God has not cast away His people whom He foreknew. Or do you not know what the Scripture says of Elijah, how he pleads with God against Israel, saying, 3 “Lord, they have killed Your prophets and torn down Your altars, and I alone am left, and they seek my life”? 4 But what does the divine response say to him? “
I have reserved for Myself seven thousand men who have not bowed the knee to Baal.” 5 Even so then,
at this present time there is a remnant according to the election of grace. 6 And if by grace, then
it is no longer of works; otherwise grace is no longer grace. But if
it is of works, it is no longer grace; otherwise work is no longer work.
7 What then? Israel has not obtained what it seeks; but
the elect have obtained it, and the rest were blinded.
Israel’s Rejection Not Final
11 I say then,
have they stumbled that they should fall? Certainly not! But through their fall, to provoke them to jealousy, salvation
has come to the Gentiles. 12 Now if their fall
is riches for the world, and their failure riches for the Gentiles, how much more their fullness!
13 For I speak to you Gentiles; inasmuch as I am an apostle to the Gentiles, I magnify my ministry, 14
if by any means I may provoke to jealousy those who are my flesh and
save some of them. 15 For if their being cast away
is the reconciling of the world, what
will their acceptance
be but life from the dead?
19 You will say then,
“Branches were broken off that I might be grafted in.” 20 Well
said. Because of unbelief they were broken off, and you stand by faith. Do not be haughty, but fear. 21 For if God did not spare the natural branches, He may not spare you either. 22 Therefore consider the goodness and severity of God: on those who fell, severity; but toward you,
goodness, if you continue in His goodness. Otherwise you also will be cut off. 23 And
they also, if they do not continue in unbelief, will be grafted in, for God is able to graft them in again.