Paul stresses that the blessing God gives us in Christ is spiritual. A contrast is probably intended with Old Testament days when God’s promised blessings were largely material. It is true Jesus promised his followers some material blessings, for he forbade them to be anxious about food, drink, and clothing, and assured them that their heavenly Father would supply their needs if they put the concerns of his rule and righteousness first.
Christians affirm with gratitude and joy that God has blessed us in Christ with every spiritual blessing. That is, every blessing of the Holy Spirit has been given us by the Father if we are in the Son. No blessing has been withheld from us. Of course we still have to grow into maturity in Christ, be transformed into his image, and explore the riches of our inheritance in him. Of course, too, God may grant us many deeper and richer experiences of himself on the way. Nevertheless, if we are in Christ, every spiritual blessing is ours already.
But note the statement “he chose us in him.” God put us and Christ together in his mind. He determined to make us (who did not yet exist) his own children through the redeeming work of Christ (which had not yet taken place). It also arose from his entirely unmerited favor, since he chose us “to be holy and blameless before him.” This means that when he chose us, we were unholy and blameworthy, and therefore deserving not of adoption but of judgment. So this is no cause for boasting.
Now everybody finds the doctrine of election difficult. “Didn’t I choose God?” somebody asks, and we must answer, “Yes, indeed you did, and freely, but only because in eternity God had first chosen you.” Scripture nowhere dispels the mystery of election, and we should beware of any who try to systematize it too precisely or rigidly.
The truth of God’s election, however many its unresolved problems, should lead us to righteousness, not to sin; and to humble adoring gratitude, not to boasting. Its practical consequences should always be that we live on the one hand “holy and blameless in his sight” (v. 4) and on the other “to the praise of his glorious grace” (v. 6).
From Reading Ephesians with John Stott by John Stott with Andrew T. Le Peau.