The process of joining the scion (shoot, twig) of a tree known to produce good fruit with the stock of another tree bearing inferior fruit so as to bring about a permanent union. Often grafting is done with a view to combining the advantageous characteristics of both scion (its good fruit) and stock (its vigor and strength). After grafted-in branches are established, though deriving nourishment from a different stock, they will produce the same kind of fruit as the tree from which they were taken.

The apostle Paul, writing to Christians in Rome, compared non-Jewish Christians to the branches of a wild olive that were grafted into the garden olive to replace natural branches that had been broken off. Such a procedure in grafting he described as “contrary to nature.” The natural branches corresponded to the Jews who, because of their lack of faith, lost out on their opportunity to be among those in line for Messiah’s heavenly Kingdom. The grafting of wild olive branches, or non-Jewish Christians, into the garden olive to replace “natural branches” was no reason for those Gentiles to have lofty ideas, for only by faith could they maintain their position. Also, the grafting of branches from the wild olive into the garden olive illustrates the permanent union that has been effected between Jews and Gentiles as fellow members of “the Israel of God.”​—Ro 11:17-24; Ga 3:28; 6:16; compare Joh 15:1-6; see OLIVE.