but if I wait long, that you may know how men ought to behave themselves in the house of God, which is the assembly of the living God, the pillar and ground of the truth.
The second (architectural) figure is of a pedestal that supports something set on top of it. "Pillar and support" is a hendiadys for "supporting pillar [foundation]." Each local church supports the witness of each believer in it and holds that testimony up before the world in which untruth abounds. Paul did not elaborate how it does this here, though the models suggested by the terms "shepherd" ("pastor"), "elder," "overseer," and "deacon" provide some clues. [Note: See A. Duane Litfin, "The Nature of the Pastoral Role: The Leader as Completer," Bibliotheca Sacra 139:553 (January-March 1982):57-66.] What the believer proclaims is the "truth," the whole truth God has revealed in His Word, but especially God’s redemptive plan.