Thomas R. Schreiner, Paul, Apostle of God’s Glory in Christ: A Pauline Theology (Downers Grove, IL: IVP, 2006), 19-20, on how “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.