Jehovah God terminated his covenant relationship with Israel as a nation because of its unfaithfulness and its national rejection of his Son.(Mt 21:42, 43; Heb 8:7-13) Evidently the apostle refers to this when saying that the casting of them away meant reconciliation for the world(Ro 11:15), for as the context shows, the way was thereby opened for the world outside the Jewish community or congregation. That is, the non-Jewish nations now had opportunity to be joined with a faithful Jewish remnant in the new covenant as Gods new nation, spiritual Israel.(Compare Ro 11:5, 7, 11, 12, 15, 25)<quoted text>
Yet Jesus preached only to Jews, instructed the disciples to preach to the Jewish communities around the known world (there were Jewish settlements from Spain to Africa to India) and said to walk away from those who didn't want to listen to Jesus' message of Jewish reformation.
Just another case of Paul contradicitng Jesus.
As Gods covenant people, his special property(Ex 19:5, 6; 1Ki 8:53; Ps 135:4), the Jewish people had enjoyed a measure of reconciliation to God, though still in need of full reconciliation by means of the foretold Redeemer, the Messiah.(Isa 53:5-7, 11, 12; Da 9:24-26)
The non-Jewish nations, on the other hand, were alienated from the state of Israel and strangers to the covenants of the promise, and . . . had no hope and were without God in the world, for they had no recognized standing with him.(Eph 2:11, 12)
In harmony with the sacred secret regarding the Seed, God nevertheless purposed to bring blessings for persons of all nations of the earth.(Ge 22:15-18) The means for doing this, Christ Jesus sacrifice, therefore opened the way for those of the alienated non-Jewish nations to come to be near by the blood of the Christ.(Eph 2:13) Not only this, but that sacrifice also removed the division between Jew and non-Jew, for it fulfilled the Law covenant and took it out of the way, thereby allowing Christ to fully reconcile both peoples in one body to God through the torture stake, because he had killed off the enmity [the division produced by the Law covenant] by means of himself. Jew and non-Jew now would have the one approach to God through Christ Jesus, and in course of time, non-Jews were brought into the new covenant as Kingdom heirs with Christ.(Eph 2:14-22; Ro 8:16, 17; Heb 9:15)