Christ is the mystery of godliness incarnate and is revealed in God's Church (Col. 1:26-27).
In opposition, the mystery of iniquity also produces a church called "the man of sin." The man of sin ultimately paves the way for the mystery of iniquity incarnate, Satan personating Christ's second coming. Each mystery produces a church, and both of these churches collide in the end, but God's people will prevail.