Paul sees a contrast between the old Israel and the new Israel. He notes that “For not all who are Israel are Israel, nor are they all children of Abraham because they are his descendants” (9:6-7). The new Israel is the Christian movement while the old Israel are those Jews related to Abraham simply by blood. This distinction is emphasized when he says “[f]or I could wish that I myself were accursed and separated from Christ for the sake of my brothers, my kin according to the flesh.” (9:3). This indicates that the Jews by blood are separate from Christ and hence “accursed.” In the place of these Jews there is a new people both composed of Jews by blood and gentiles. He says “as indeed it says in Hosea: ‘Those who were not my people I will call my people, and her who was not beloved I will call beloved’” (9:25). A new people is selected, on this reading of Hosea, to replace the old. It should be emphasized that not all Jews by blood are excluded. Paul remarks that “[i]nasmuch as I am the apostle to the Gentiles, I glory in my ministry in order to make my race jealous and thus save some of them” (11:13-14). Jews are not saved, it would seem, except through this new movement. Paul also provides a parallel situation in which Elijah points out the sins of the Israelites but God selects a set of elect that will still be saved (11:2-5). There are certain Jews who will receive justification in Messiah but Judaism itself is no longer adequate.
It is clear that for Paul Israel is still accepted by God. Paul argues: “I ask then, has God rejected his people? Of course not! For I too am an Israelite, a descendant of Abraham, of the tribe of Benjamin” (11:1). It is very clear in the statement that the People of God have not been rejected and by this statement Paul means that since he comes from Judaism his ministry is an extension of Judaism. Paul provides a parallel situation in which Elijah points out the sins of the Israelites but God selects a set of elect that will still be saved (11:2-5). From Judaism a special elect movement has emerged. “What then? What Israel was seeking it did not attain, but the elect attained it; the rest were hardened” (11:8). Israel, i.e. the original Jews did not find salvation but from the elect of Judaism it was discovered. This is made most clear in the metaphor about the branches: “[b]ut if some of the branches were broken off, and you, a wild olive shoot, were grafted in their place and have come to share in the rich root of the olive tree, do not boast against the branches. If you do boast, consider that you do not support the root; the root supports you” (11:17-18). Judaism is the original tree, the root, of the new movement. From Judaism the movement emerged and has significance. It is not a rejection of Judaism but rather a new manifestation of it.
The first paragraph seems weak in that it emphasizes the fact that a connection by flesh or blood is inadequate but that does not in itself mean that Judaism is rejected. It fails to express a categorical rejection of Judaism but only indicates that some Jews have failed in obtaining salvation. The second paragraph in the meantime emphasizes that the new movement comes from Judaism and so Judaism is not rejected but the fact that the new movement is derived from Judaism does not in itself prove that the new movement does not throw out a lot of the old. The way Acts represents the controversy over allowing non-Jews in the movement may shed some light on this. It would seem that at the very beginning the movement remained a fundamentally Jewish thing. However, the way the Gospels depict the people rejecting Jesus at before his crucifixion might provide some support for the thought that the early participants in the movement saw themselves as separate from this movement. On the whole I think that the idea that the movement is part of Judaism, at least at this stage, is more persuasive because there is a constant need to explain Jesus in terms of existing Jewish thought. The constant citations of Scripture and the way various authors explain Jesus in relationship to Judaism show that they thought of themselves as still part of this movement. One question that remains, though, is a question of degree. To what extent did these early followers of Jesus feel the need to relate to Judaism and to what degree did they feel at liberty to differ from it. Accepting Gentiles and telling them they did not need to follow the Torah is at odds with Judaism, but at the same time these things are justified by reference to Judaism.