'Grafted' in the Bible

And if some of the branches have been pruned away, and you, although you were but a wild olive, have been grafted in among them and have become a sharer with others in the rich sap of the root of the olive tree,

"Branches have been lopped off," you will say, "for the sake of my being grafted in."

Moreover, if they turn from their unbelief, they too will be grafted in. For God is powerful enough to graft them in again;

and if you were cut from that which by nature is a wild olive and contrary to nature were grafted into the good olive tree, how much more certainly will these natural branches be grafted on their own olive tree?