The Israel of God is the whole body of God's elect, Jew and Gentile, who must be saved (Rom. 11:26). When Paul says, "All Israel shall be saved," he is simply declaring that the whole purpose of God regarding the salvation of his elect must be fulfilled. Not one of the chosen can ever be lost. Certainly, he is not talking about the salvation of all national Israel, or of all Abraham's physical seed. Many of them have already perished! He is not asserting that all the physical descendants of Abraham living at the time of Christ's second coming will be saved when they see his appearing. Nowhere in the Bible does God promise salvation to people who physically see Christ! Salvation is promised only to those who look to Christ in faith (Isa. 45:22).
The Israel of God is the church of God, the kingdom of God. It is a holy, spiritual nation (I Pet. 2:9), not an earthly, political nation. The Israel of God is the household of faith. If you are born of God, if you trust the Lord Jesus Christ, you are a child of Abraham (Gal. 3:6-9, 29). "He is not a Jew, which is one outwardly...But he is a Jew, which is one inwardly" (Rom. 4:28-29). The promises of God are not made to Abraham's physical seed, or to any upon the basis of earthly distinctions (John 1:13), but to Christ, his spiritual seed, and to all who are in him. The adoption, the covenant, the glory, and the promises of God pertain not to the physical seed, but to the spiritual, to the Israel of God.
The Israel of God is the true circumcision, the saints and people of God have three things in common, three identifying characteristics by which they are known (Phil. 3:3). (1) They worship God in the Spirit. They worship him in a spiritual manner, in their hearts, without the use of carnal objects (icons and idols), by the power and grace of the Holy Spirit. (2) They rejoice in Christ Jesus. They trust the Lord Jesus Christ alone as their Savior in whom they have complete acceptance with God (I Cor. 1:30). And (3) They have no confidence in the flesh. They do not trust their pedigree, performances, or piety, but Christ alone! The Israel of God is that body of elect, redeemed, regenerate men who live before God by the power of the cross, Christ crucified, and by the rule of the cross.
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