In this short passage, Paul says a lot about God, especially what He has done for our glorious redemption. But what is one unmistakable message conveyed throughout this whole passage? That, from before the foundation of the world to all eternity, God’s work of redemption is “in Christ.” But there is another message that is equally unmistakable: God does all things to the praise of His glory.
A long list of God’s goals mentioned in this passage can be divided into two categories: secondary and primary. His secondary goals are: choosing us that we should be holy and blameless before Him (v. 4); predestining us to adoption as sons (v. 5); summing up all things in Christ (v. 10); working out all things after the counsel of His will (v. 12); sealing us in Christ with the Holy Spirit and redeeming us as His possession/people (v. 14).
God accomplishes all these secondary goals for His primary goal: to the praise of His glory. You can’t miss it: “he predestined us for adoption as sons through Jesus Christ, according to the purpose of his will, to the praise of his glorious grace, with which he has blessed us in the Beloved” (vv. 5-6); “In [Christ] we have obtained an inheritance, having been predestined according to the purpose of him who works all things according to the counsel of his will, so that we who were the first to hope in Christ might be to the praise of his glory” (vv. 11-12); “In [Christ] you also, when you heard the word of truth, the gospel of your salvation, and believed in him, were sealed with the promised Holy Spirit, who is the guarantee of our inheritance until we acquire possession of it, to the praise of his glory” (vv. 13-14).