What is this mystery? It is that God purposed to recapitulate all things in the Lord Jesus Christ. The Son of God came, became incarnate, suffered, died, rose, ascended into heaven, and, as God-man, became Head of all things, both heavenly and earthly.
Of these actions of the incarnate Son of God, almost all are evident in themselves. There is nothing particular to explain about them, for all is clear from the Incarnation to His sitting at the right hand of the Father.
What, then, is not evident? The recapitulation of all things in this God-man who sits at the right hand of the Father.
This is precisely the mystery hidden in God, which could have remained unrevealed without harm to the work of salvation. God revealed it only according to the excess of His grace. By this revelation He made the already great riches of His grace abound still more.
The Apostle is chiefly occupied with this mystery throughout the whole epistle. It is this that he has in mind here. St. Chrysostom says: "The mystery is that man has been seated on high." But by this the recapitulation of all things has been accomplished.
"According to His good pleasure." This either expresses the same thing as the words above, "according to the good pleasure of His will." There was no necessity at all to tell this mystery. God's good pleasure alone was pleased to tell it.
St. Chrysostom says: "This was His strong and heartfelt desire, somehow to tell us the mystery of His will."
God purposed to grant us so many blessings in the Lord Jesus Christ. Taken together, they express or constitute God's good pleasure toward us. According to this fullness of good pleasure, He also told the mystery of His will concerning the recapitulation of all things in Him.
He did so according to that law of goodness of which the Apostle speaks elsewhere: "How shall He not also with Him freely give us all things?" (Rom 8:32).
Or, since such good pleasure had already been mentioned in this same point, for it is all one point, it is permissible here to read: concerning, or with respect to, His good pleasure, which God purposed in the Lord from the beginning, from eternity.
What God purposed to accomplish through the Lord for our salvation is almost all evident, and took place before the eyes of all.
But the mystery of God's will in all this good pleasure toward us is what must result from it at the end of all things, having been marked out from the beginning. The final goal of all this was hidden in God.
This mystery, concerning all His good pleasure toward us, He told according to the excess of grace. That is, He revealed that all this is being done so that He might recapitulate all things in the Lord.