1. The church is grafted into the olive tree, which stands for the nation of Israel, and not the other way around, which erroneously has Israel being grated into the roots and the trunk of the church (Ro 9–11). The believing church is grafted into the roots and trunk of the olive tree of Israel. Without the roots and trunk of the tree, which represent the nation of Israel, the church has no anchoring or rootage in space and time or history.
2. The new covenant of Jeremiah 31:31–34 was explicitly made with “the house of Israel and the house of Judah”; it was not a covenant made with the church, even though the church may share in it, just as it shares in parts of the Abrahamic-Davidic covenant(s). There is no specific covenant in Scripture directly made for, or with, the church in either Testament!
3. Ever since the beginnings of human history, God has been raising up a remnant from all over the human race. The present-day believing church is part of that faithful remnant, which ever since Pentecost has been grafted into the trunk of the tree identified as Israel. Thus, there are distinguishable aspects between Israel and the church, just as there is a distinguishable aspect in the program of God, but there is not a separation, or a sharp division, between “the people of God” or the “kingdom of God.” The continuity term for believing Israel and the church is the one “people of God,” just as the continuity term for the one program of God is the “kingdom of God.” (Walter C. Kaiser Jr. The Promise-Plan of God: A Biblical Theology of the Old and New Testaments. Grand Rapids: Zondervan, 2008, 27)