Summary: Paul explains how the church is a really "big deal" in the plan of God and how it should, therefore be a "big deal" to us.
A word that Paul uses in our passage for today is one that he also uses elsewhere in this book. That word is “mystery. The word “mystery,” is used by Paul in verses 3, 4, 6, & 9. What is Paul referring to when he uses this word?
The word, “mystery” might make us think of Agatha Christie, Sherlock Holmes or Perry Mason. We usually think of a mystery as something to be figured out, a puzzle, or an enigma. But the word used by Paul has a different meaning. The Greek word “musterion,” as used here by Paul, means: “something which is beyond natural knowledge, but has been opened to us by divine revelation through the Holy Spirit.”
We come up with this definition for the word Paul uses here from his own writing in the book of Colossians, as well as verse 3 of our text:
As Paul elaborates on this “mystery,” this truth that has been opened to us by divine revelation through the Holy Spirit, he speaks of the church. He speaks of the church as being something which was previously undreamed of as a possibility, but which is now, has become a reality.
In the church, God has done away with all previous distinctions and has created a new humanity.
“For he himself is our peace, who has made the two one and has destroyed the barrier, the dividing wall of hostility, by abolishing in his flesh the law with its commandments and regulations. His purpose was to create in himself one new man out of the two, thus making peace, and in this one body to reconcile both of them to God through the cross, by which he put to death their hostility. He came and preached peace to you who were far away and peace to those who were near. For through him we both have access to the Father by one Spirit.” - Ephesians 2:14-18 (quickview)  (NIV)
Paul tells us, therefore,, that the church is a very “big deal” as far as God is concerned. The church is at the heart of His redemptive work and His eternal purpose (vs. 10-11). As part of this new humanity, through faith in Christ, we are involved in a cosmic drama.
The theater is history. The stage is the world. The actors are the church (you and me). The writer is God, who also directs and produces the drama.
As producer, He has paid the price (through the death of His Son) to earn the right to decide how things are to be done. As director, He gives the orders that are to be acted out by His church (the actors in this cosmic drama).
The audience is the elect angel host of heaven and the fallen angels of hell.
“It is through the old creation (the universe) that God reveals His glory to humans; it is through the new creation (the church) that God reveals His glory to the angels.” - John R.W. Stott, God’s New Society