To a large degree, chapter one is an introduction to the letter. In the first two verses, Paul identifies himself and addresses his recipients in his usual style, and then he jumps into his introduction beginning in verse 3.
These verses can be summed up as words of praise and thanksgiving, words that are difficult to read without feeling the passion and excitement that Paul and his recipients must have felt; whatever you do, don’t take them for granted:
Praise be to the God and Father of our Lord Jesus Christ, who has blessed us in the heavenly realms with every spiritual blessing in Christ. (v. 3)
Have you ever really reflected on this verse? Read it again slowly and let it sink in…
This is one of those “wow” moments!
For he chose us in him before the creation of the world to be holy and blameless in his sight. In love he predestined us for adoption to sonship through Jesus Christ, in accordance with his pleasure and will— to the praise of his glorious grace, which he has freely given us in the One he loves. In him we have redemption through his blood, the forgiveness of sins, in accordance with the riches of God’s grace that he lavished on us. With all wisdom and understanding, he made known to us the mystery of his will according to his good pleasure, which he purposed in Christ, to be put into effect when the times reach their fulfillment—to bring unity to all things in heaven and on earth under Christ.
In these verses, Paul gives us a thumbnail sketch of the letter; you can see our redemption all though the passage. You can also detect the purpose for this great salvation in the last two verses, for God’s grace came for a purpose that goes all the way back to Genesis, the purpose for which He created us in the first place. Even though things went crossways in the garden when Adam and Eve sinned, God desires to bring all things back together under the banner of Jesus Christ, and for this reason He saw fit to devise a plan of redemption for as many as will respond, a plan for which the elect are predestined.
I must point out here that many good Christians have been willing to make mischief with the concept of selection and predestination, usually putting things together in a way that results in their having been predestined, and most of the rest of us not. Naturally, we aren’t going to venture into divisive mischief here. Paul, it seems to me, is talking here about all of those who have responded to God’s grace, for are we not “predestined” to great things in Christ?
At any rate, I think that this glorious passage is best left for each to reflect upon, after all what could I possibly add to these words? No, they are best left to our individual worship and prayer time, for they will fill your day with glory and thanksgiving.