Dr. Thomas Schreiner on "The Israel of God" in Galatians 6:16

In his Galatians commentary, Dr. Thomas Schreiner [who was my professor for a Greek exegesis class on Galatians] writes about the phrase "the Israel of God" from Galatians 6:16. Dr. Schreiner begins his discussion of this phrase with the following observations:

The last words of Gal 6:16, "even upon the Israel of God," could be interpreted to refer to ethnic Israel or to the church of Jesus Christ. Scholars dispute whether Paul refers (1) to a remnant of Jewish believers within the church of Jesus Christ, or (2) to Gentile believers (along with Jewish believers) who constitute the new people of God-- the new and true Israel. If the reference is to ethnic Israel, it is limited to Jewish believers in Christ, for it is "the Israel of God," not merely ethnic Israel.

Schreiner next offers some arguments from those who take the first view mentioned above, and he raises questions about these arguments. Then he presents the following case for understanding "the Israel of God" in Galatians 6:16 to refer to all believers, both Jewish and Gentile. [The remainder of this post is quoted from Schreiner's Galatians commentary, pages 382-383]:

...in 1 Cor 10:18 Paul speaks of (lit.) "Israel according to flesh," which at least suggests that there may be a contrast between Israel according to the flesh and Israel according to the Spirit, and the latter could possibly include Gentile Christians. The term "Israel" is not decisive in any case, for context as always must be determinative, and here the arguments for Israel referring to the church of Jesus Christ, made up of both Jews and Gentiles, are compelling.

The key question in Galatians is whether one must become a Jew and be circumcised to belong to the people of God. Must one receive circumcision to belong to the family of Abraham? The false teachers argued that circumcision and observance of the law were required to be part of Abraham's family. But Paul has argued throughout the letter that circumcision is unnecessary and that those who put their faith in Christ belong to the family of Abraham. When he speaks of "the Israel of God" at the conclusion of the letter, where he rehearses the major themes of the letter, he is driving home the point that believers in Christ, members of the new creation, are the true Israel.

Such an interpretation fits with the whole of the letter, for believers in Christ are the true sons of Abraham. But if they are Abraham's children and belong to his family, then they belong to the Israel of God. It would be highly confusing to the Galatians, after arguing for the equality of Jew and Gentile in Christ (3:28) and after emphasizing that believers are Abraham's children, for Paul to argue in the conclusion that only Jews who believe in Jesus belong to the Israel of God. By doing so a wedge would be introduced between Jews and Gentiles at the end of the letter, suggesting that the latter were not part of the true Israel. Such a wedge would play into the hands of his opponents, who would argue that to be part of the true Israel one must be circumcised.

Instead, Paul confirms one of the major themes of the letter. All believers in Christ are part of the true Israel, part of God's Israel. This fits with what Paul says elsewhere when he says believers are the true circumcision (Phil 3:3). Since believers in Christ are the true family of Abraham and the true circumcision, they are also part of the true Israel.

...the decisive argument for seeing the church as the Israel of God is the argument of Galatians as a whole.