When you examine the Bible, you see the main characters are GOD (his Christ), Satan (his Antichrist, i.e. instead of Christ), Israel, and the nations who bless or curse her people or her land. We Christians try to make it all about us and yes, although we are saved by the blood and Grace of Jesus (Yeshua), we are grafted into that Olive Tree through Jesus Christ.
The Olive Tree represents the Spiritual Promises made to Abraham by God, who through Jesus Christ is also the root of this tree, as well as the branch and off spring of David. This, as Paul calls it, is the Commonwealth of Israel.
Commonwealth: an independent country or community, especially a democratic republic.