Paul’s illustration of grafted in branches is contrary to nature and agricultural practices.
The natural process is to take a shoot from an olive tree that bears good fruit though it is not strong and graft it into a wild olive tree whose fruit is poor but which grows strongly. The result is a tree with vigorous growth that bears good olives.
But Paul suggests the reverse to impress upon the Gentiles their dependence upon the root.
And if some of the branches were broken off, and you, being a wild olive tree, were grafted in among them, and with them became a partaker of the root and fatness of the olive tree, do not boast against the branches. But if you do boast, remember that you do not support the root, but the root supports you.
This passage continues to clarify that the Holy Root is God. It is God that sustains and supports both Jews and Gentiles.
But there is much more in this passage. Paul was addressing the attitude of the early Gentile Believers, still prevalent today, that the Gentiles had replaced the Jews as God’s “Chosen People” and were superior in all ways. Of course this too is contrary to God’s unique relationship with Israel.
PRAY THAT THE GENTILE CHURCH WILL HUMBLE ITSELF BEFORE GOD AND REPENT FROM ALL FEELINGS OF SUPERIORITY OVER THE JEWS.