Here is Thomas R. Schreiner's proposal for the 'center' of Paul's theology:
The image of a house may help us visualize the heart and soul of Pauline
theology. ...The illustration of a house is used here because it is suggestive
in conceiving of Paul's theology not because Paul himself supplies such an
illustration. No analogy fits perfectly when we try to communicate the Pauline
gospel. Visualizing Paul's thought in terms of the building of a house provides
an entry point into Paul's thought, a doorway through which we can enter into
his worldview.The foundation of the house is God himself. From him the house
takes its shape, and it is utterly dependent on him for its growth. The house in
this illustration represents God's saving plan in history, and that plan
includes the role of church in history. God is the foundation for all that
occurs, 'because from him and through him and for him are all things. May the
glory be his forever' (Rom 11:36). ...One advantage of thinking of God as the foundation is that the other teachings of Paul are not then conceived as concentric circles that are farther and farther from the center. Whether Paul thinks of justification, reconciliation or sin, they are all based on the foundation; they are not separate from the foundation, nor are they far removed from it. They are themes that frame the house and give it detail, but all these themes depend on the foundation. Since God is the foundation of the house and it depends on him for its survival, he deserves honor for the building of the house.
...Such an illustration also highlights the importance of salvation history, what is often called the 'already but not yet' dimension of Pauline theology. When we speak of salvation history, we think of the fulfillment of God's saving plan and promises. The fulfillment of God's plan in history is announced in the Pauline gospel. The promises made to Israel in the Old Testament have now become a reality in and through the ministry, death and resurrection of Jesus Christ. God's saving promises are already a reality for the believer in Jesus Christ...On the other hand, believers still await the consummation of salvation history... Salvation history, then, could represent the remodeling of the house, for the new covenant fulfills what was promised in the old (Jer 31:31-34; 2 Cor 3:4-18). The image of 'remodeling' is misleading if it suggests that God 'starts over' with the church. Perhaps we should think of the Old Testament as the framing of the house and think of the fulfillment of salvation history as the completion of the inside of the house...Hence, the image of the house nicely captures various dimensions of Paul's theology-the foundation is God and Christ, salvation history portrays the progress being made on the house, and the theme of the house is the gospel.(Paul, Apostle of God's Glory in Christ; 19-20)
Well, what does one make of this 'center' in comparison to Thielman's? Thielman, if one remembers, stresses that in order to flesh out the 'center' of Paul's theology, Paul himself must be explicit in its importance to him. On the other hand, Schreiner states that the illustration of a house is not one in which Paul himself uses, but rather is useful for illustrating the 'center' of Paul's theology. Both are in agreement that themes such as justification cannot solely be the center of Paul's gospel. For Thielman 'justification by faith' is too specific to be helpful, and for Schreiner justification is one of the frames of the house, but God and Christ are alone the foundation. For Thielman "God's graciousness toward his weak and sinful creatures" summarizes the center of Paul's theology (232), while Schreiner maintains that the house imagery captures the various foci of Pauline theology, namely God and Christ, the fulfillment of OT promises in Christ, and the gospel of God which is the "theme of salvation history" (e.g. Rom 1:1; 20).
Let me ask my fellow bibliobloggers to weigh in. What are the strengths and weaknesses of both Thielman's and Schreiner's observations on the center of Paul's theology?