The Bible is full of metaphors and analogies and similes. Many of them are agricultural in nature—chaff and wheat, shepherds and sheep, branches and vines. If you grow up in the church this really isn’t a problem, because you are taught the meaning at such a young age. But if you didn’t grow up in the church (or weren’t paying attention) and weren’t a farmer and shepherd from the Mediterranean Sea than much of what the analogies will go right over your head.
We see this in Romans 11 where Paul is finalizing his “God is for Jews and Gentiles” argument. The first twelve verses reiterate the point that Jews, Paul’s people, still belong to God by his Grace. Then Paul launches into metaphor of branches and olive trees. He compares the Gentiles to wild olive branches that are grafted onto the olive tree. He reminds the Gentiles not to boast or lord it over Jews who do not follow Jesus, because it is only in faith that they are grafted on. And heck, he says, God may graft them back on before the end.
This is a relatively common metaphor in the Bible and in the modern church. Even though so few of us know what grafting a branch on really entails, we employ the metaphor all the time, because, well, it’s in the Bible. I think a different (not necessarily better) way is to imagine a prestigious university. Let’s pretend that this university is in South Dakota and you are from India. Growing up you had no connection to that university, because you lived so far away (physically and culturally). You may have heard about it because it really is the best university in the world, but you didn’t know anything. Then out of the blue one day you get an invitation to attend this school in South Dakota. Your wildest dreams, which you didn’t even you were your dreams, are being fulfilled. You go to that university and the first day you step on campus you are now part of a great history. Even though you just joined and knew nothing about the school, now you can take pride in what happened 50 years ago or in the Nobel Prizes won 10 years ago. The university’s history is now part of your history, even though you had nothing to do with it. You are still Indian, but you also are part of this university.
So it is with Paul and Gentiles the branches and the olive tree.