Luther Burbank was a genius. As a horticulturist, he is credited with the creation of over 300 different varieties of plants, most notably the Shasta daisy and the blight-resistant Burbank potato. Although the term did not exist at the time, and if it had it would not have carried the negative connotations of today, he was one of the masters of creating Genetically Modified Organisms (GMOs). Rather than working on the molecular level, though, most of his modifications came through time-honored methods such as cross-breeding and grafting. He took these methods to a new level, based on the theories of Charles Darwin, but they had been around for millennia.
Driving along the highways of northern California, one can see rows of strange-looking walnut trees. The lower three or four feet of the trees are almost black, but the upper portions are a light brown. These are English walnuts, grafted onto a black walnut root stock. The native black walnut trees are more disease-resistant, and grow well because they are native to that soil and climate zone. The English walnuts, however, are more desirable for their flavor and softer shell. Grafting is the answer to growing English walnuts in the northern California climate. This is an ancient practice, and was even familiar to the apostle Paul and his readers.
And if some of the branches be broken off, and thou, being a wild olive tree, wert graffed in among them, and with them partakest of the root and fatness of the olive tree; Boast not against the branches. But if thou boast, thou bearest not the root, but the root thee. Thou wilt say then, The branches were broken off, that I might be graffed in. Well; because of unbelief they were broken off, and thou standest by faith. Be not highminded, but fear: For if God spared not the natural branches, take heed lest he also spare not thee. Behold therefore the goodness and severity of God: on them which fell, severity; but toward thee, goodness, if thou continue in his goodness: otherwise thou also shalt be cut off. And they also, if they abide not still in unbelief, shall be graffed in: for God is able to graff them in again. For if thou wert cut out of the olive tree which is wild by nature, and wert graffed contrary to nature into a good olive tree: how much more shall these, which be the natural branches, be graffed into their own olive tree? (Rom 11:17-24, KJV [graffed=grafted])
This passage is often used to establish that the church of Christ is “spiritual Israel.” But is that what Paul is truly arguing? The entire letter is written to reconcile Jewish and non-Jewish believers into a new unity, not an old one. God is Burbank trying to create a new fruit.
But what about the passage about grafting? Paul says that Israel became branches “broken off” of the olive tree. The tree, then, was older growth than even Israel. The branches are not the root stock. In chapter 4, Paul declares Abraham to be the root stock. Israel can be grafted in “if they abide not still in unbelief.” That is, whether non-Israel or Israel, the condition for grafting in to the good olive tree is faith.
Gentiles do not have to become Jewish to follow Christ. Jews do not have to become non-Jewish to follow Christ. The faith that grafts one into the church is a matter of trust, not law. We are not “spiritual Israel.” We are the church that was planned before Israel, before Abraham, and before Adam.