Paul speaks in a brilliant chiasm, exposing his Hebraic-based message for his mostly Gentile audience. The big idea is in the middle – the musterion. This rich Old Testament idea was being abandoned for mystery religion nonsense, so Paul reestablishes the right meaning for the term. The ancient and rich truth is that Gentiles are also chosen for glory. Paul also describes his goal of spiritual maturity and his willingness to suffer and fight in God's strength so that people grow up well in Christ.