and if the root is holy, so are the branches.
Paul has spoken of Israel’s future spiritual restoration in verses 12 (“their fullness”) and 15 (“their acceptance”). God’s faithfulness to his promises is one spiritual principle—the most important one—that explains the divine plan to restore that nation. But is there another, related spiritual principle that can add further explanation? Yes, and Paul finds that principle in the two metaphors in this verse.The firstfruits and whole lump
God wanted the people of Israel after they took up residence in the promised land to remember that he alone is the provider of all good things. So every time they harvested grain from the field and mixed dough for bread, they were to set aside a small portion to give to the priests (Numbers 15:17–21). This small lump was set aside for the Lord and therefore declared holy. Paul has in mind the principle that the holiness of the “firstfruits” extends to the “whole lump.”
This principle—that the part sanctifies the whole—seems clear enough, but commentators divide over the identity of the part. Which set of people did Paul have in mind? Some scholars (Douglas Moo, Colin Kruse, Craig Keener, Marvin Vincent, Archibald Robertson) think they are the patriarchs of Israel, beginning with Abraham. It was his faith that set him apart as the first of the believing remnant. Isaac and Jacob can also be included. Other commentators (Charles Cranfield, Everett Harrison, Joseph Fitzmyer, Richard Longenecker) believe Paul had in mind the believing Jewish remnant.
In either case—patriarchs or faithful remnant—the people of faith, few as they might be, are the firstfruits who serve to guarantee that God will fulfill his promise to the whole lump, the future nation when it is saved.The root and the branches
In this second metaphor, all the above scholars see the “root” as standing for the patriarchs. In support of this interpretation, verse 28 says God loves Israel “because of the fathers.” The principle is essentially the same as with the first metaphor—that the holiness of the root (Abraham and the other patriarchs) extends to the branches, those Jews who trust in Christ.
Paul gives this metaphor more expansive application than he gives the first, as he goes on to speak of an olive tree that pictures the salvation of both Jews and Gentiles at the end of this age. Believing Gentiles are now being added to the tree (verse 17) and later more Jews will be added (verses 23–24) as Paul sets up his conclusion that “all Israel will be saved” (verse 26).
Richard Longenecker points out that Paul uses these metaphors to proclaim the intrinsic oneness of the remnant of Jews and the remnant of Gentiles as they intermingle in the whole lump and on the tree. In Christ the two are one new man and one body (see Ephesians 2:14–18).
Scholars such as Fitzmyer and Harrison who see the firstfruits as one category (the faithful remnant) and the root as another (the patriarchs) think Paul links the first metaphor with the chapter’s preceding context and the second metaphor with the context that follows. In their view, Paul looks backward to Paul’s prior discussion of the remnant and forward to the extended metaphor of the olive tree, whose root is clearly the patriarchs.The meaning of “holy”
Paul calls both the firstfruits and the root holy, making the whole lump and the branches holy as well. This word has two meanings. Its primary sense—the meaning here—is of people and things separated and consecrated to God. The firstfruits and root are therefore set apart as belonging to God. The word also has a technical sense of set apart for salvation. That is not the meaning here. Moo explains:
In the context of what Paul has said previously, the word holy does imply Israel’s future restoration, but confirmation of that destiny will come in the following verses. This verse asserts that God has a role to play for corporate Israel, and we know from the context that this role will consummate in the salvation of many Jews. Nevertheless, Paul is not suggesting that every Jew in the end will be saved. Salvation is for whosoever believes.