NOTES for Eph 3:14-21
From speaking about God's new people, Paul turns to spiritual life. It is, of course, no accident that he calls the Church the body of Christ and speaks of Christians as parts of that body. Clearly, this is neither an allegory nor a unity of ideas. The faithfulness of the faithful makes possible that essential, organic unity of Christians with Christ which the apostle describes as Christ's “dwelling” in His followers' hearts. This image recalls another, associated with the prophetic tradition: the prophets also often spoke of God's breath, or spirit, entering a person's heart. For Paul, Christ's dwelling in the hearts of the faithful is evidently inseparable from their life in the Kingdom, in which they cannot otherwise take root (vv. 14–19).
Of course, the apostle does not raise this subject by chance in the context of his reflections on God's new people: it is precisely the living spiritual bond of the faithful with the risen Christ that makes them a new people. There is nothing fundamentally new in this approach. God's people have always been God's people not because of their particular religiosity or spiritual stature, but because of God's presence among them since the Exodus, the covenant at Sinai, and the giving of the Torah. Only the quality of these relationships is new. Previously, God's presence was an objective reality that shaped and spiritually renewed the lives of those ready to follow God by following the Torah.
Now Christ's presence in the hearts of the faithful depends only on the faithful themselves, not merely renewing their spiritual life but transfiguring them completely, so that at the end of time, when the Kingdom is revealed in all its fullness, they can become a full part of it, as far as transfigured human nature allows. For Paul, the messianic people are not simply a people who have accepted the Messiah. In the apostle's view, only a people sharing one life with the Messiah can become a messianic people: the life of the Kingdom, which neither Jew nor Gentile can attain without Him.