There is confusion and disagreement about who the “Israel of God” is, as described in the New Testament in Galatians 6:14-16, etc. Is it the same as Old Testament Israel? Are the Old Covenant promises to Israel unchanged, or perhaps modified by God because of Christ? Were the Old Covenant promises contingent on obedience? What does the writer of Hebrews mean by “the heavenly Jerusalem” (Hebrews 12)? What is the New Jerusalem of Revelation 21? How should we understand all of this since we are in the New Covenant era? Are the Old Covenant promises replaced by new promises in the New Covenant? How are Jews saved?
Source: Faith Facts