The hardening of Israel in Paul’s day is like the hardening of Pharaoh. They both harden themselves and are hardened by God. But Israel’s hardening is only partial. Paul says that God is making Israel jealous by fully including the Gentiles. This acts as a wake up call to the remnant in Israel and they too become full participants in Christ, just as Paul was. There is a great in-grafting of the two, the Jews and the Gentiles, together into one new body, the Church, thus completely doing away with the old-creation distinction. There is only one body now and this body is the center of the new creation in Christ.