"Israel of God" (Gal. 6:16) seems to be used here, not as a general phrase for every saint, but for the believing ones in Israel—those Jews who had repudiated their own works and found shelter only in Christ Jesus. Two parties are spoken of, and not one only. "As many as walk according to this rule" are rather the Gentile believers; and the "Israel of God" are the Jewish saints, not the mere literal Israel, but "the Israel of God"; the Israelites indeed, whom grace made willing to receive the Savior.