"The Faithfulness of Jesus Christ
It could easily pass as trite to say that Jesus Christ is the center of all of Paul's theology. Not only do all things hold together in Christ (Col.1:17), but Paul's thought coheres in Jesus Christ, and the apostle sees him as the center and fulfillment of the Scriptures of Israel. For Paul to announce that salvation is found in Jesus Christ is to make a claim about the unfulfilled promises to Abraham about the blessing of the nations. And it is to make a claim about God's redemption of the failed narrative of Israel as God's own possession and the national agent of God's blessing of the nations. Finally, reaching back in the narrative before Abraham to the failure of Adam and Eve, Jesus is the true human who renders to the creator God a faithful obedience embodied by a life of self-giving love for others. Jesus Christ, then, and his relation to the entire range of God's redemptive purposes, becomes the context within which the Christian life takes place and the template for what it involves.
First, Jesus redeems the failed narrative of Adam and Eve. Humanity was called to faithfulness to God by ruling over creation on God's behalf. Their proper God-ward, other-oriented, and creation-directed relations represented within creation the transcendent rule of God. Where humanity failed, Jesus was faithful. He took on the sin-dominated humanity that resulted from humanity's disobedience (he came "in the likeness of sinful flesh" [Rom.8:3]. and was obedient to God even to the point of a shameful death on a Roman cross (Phil.2:8). His obedience to God effects the transformation of those in Christ, returning them to God's original intention for them-to "exercise dominion in life through one man, Jesus Christ" (Rom.5:17).
Second, Jesus is the true seed of Abraham, making good God's promises to the patriarch. Paul offers a daring argument in Galatians 3:16-18. He builds on the collective singular "seed" in order to claim that Jesus Christ is the intended incipient of the Abrahamic promises. Because the Galatian gentiles are "in Christ," united to him by the Spirit of God, they are therefore children of Abraham, beneficiaries of God's promise to bless the nations through Abraham (Gal.3:14,29).
Third, and related to the second point, Jesus is the true Israelite who fulfills Israel's mission to be a light to the nations, unleashing God's blessings on all humanity and drawing the nations into the praise of the God of Israel (Ga. 3:14; Rom.15:9-12).