When God chose Israel as his special people and covenant partner, it was his intention through them ultimately to bless the world. “By your descendants,” God promised Abraham, “shall all the nations of the earth be blessed” (Gen. 22:18). God blessed Israel so that, through Israel, all nations would be blessed. The chosen people prayed: “May God . . . bless us, that thy . . . [saving power] may be known . . . among all nations” (Psalm 67:1-2). Israelites who rightly understood their role as God’s chosen people gladly invited other human beings everywhere to worship Israel’s God, saying: “Praise the Lord, all nations!” (Psalm 117:1).
This is the hope of the Old Testament, but what does it mean and what will it look like when fulfilled? God is sovereign–“king over all the earth” (Zech. 14:9). Earth is “full of the knowledge of the Lord as the waters cover the sea” (Isa. 11:9). The nations go to Jerusalem to receive instruction from God. “Many nations shall . . . say: ‘Come, let us go up to the mountain of the Lord . . . that he may teach us his ways and we may walk in his paths’” (Micah 4:2). The language is poetic; the details are symbolic, but their meanings are clear. This is a composite sketch of the kingdom of God–whether drawn within the bounds of time and space, or in the Age to Come, we cannot be certain and it really does not matter. It is a desirable situation and it is open to us.
God brings about these things through his messianic Servant. He is “a shoot from the stump of Jesse” (a descendant of David) and God’s Spirit rests on him (Isaiah 11:1-2). He is Israel’s deliverer but much more. God tells him: “It is too light a thing that you should be my servant to raise up the tribes of Jacob and to restore the preserved of Israel; I will give you as a light to the nations; that my salvation may reach to the end of the earth” (Isa. 49:6).
As it happens, these words from Isaiah 49 were used by Jesus the Messiah when he appeared to then-hostile Saul of Tarsus and called him to be his special apostle to the nations/Gentiles (Isa. 42:7, 16; Acts 26:16-18). The mystery, God’s secret, was about to become the content of public announcement. The world stood on the cusp of God’s goal for humankind. These expectations would be confirmed when the Gentile world became obedient en masse to Paul’s gospel message.
“We have received grace and apostleship,” Paul said, “to bring about the obedience of faith . . . among all the nations (Rom. 1:5). “The mystery . . . kept secret for long ages . . . is now disclosed . . . to all nations . . . to bring about the obedience of faith” (Rom. 16:25-26). The phrase “obedience of faith” is faith or trust in Christ as Savior, the obedient response for which the gospel calls. It is also the Christian’s life of obedience to God in general, the normal evidence and fruit produced by genuine saving faith within. Salvation was coming to the nations, and Paul was the chosen instrument whose labors God would use to make this dream of the prophets a reality.