Note 15 at Eph. 2:19: Gentiles were strangers and foreigners to God and His people (Eph. 2:12). A "stranger" was neither a friend nor an acquaintance but rather an outsider. "Foreigners" were aliens who were permitted to reside in a country but who lived without any rights of citizenship and who could be expelled without appeal.

Because of Christ's reconciling work of the cross, Paul now uses three metaphors in describing both the Jews' and the Gentiles' new position before God. We are now (1) fellow citizens with God's people (v. 19 [NIV]; Phil. 3:20 [NIV]), (2) of the same household (v. 19; Mt. 12:48-50; 23:8-9; Lk. 8:21; Rom. 8:29; Heb. 2:11-12; Gal. 6:10; Eph. 3:15; Phile. 16), and (3) part of God's building (v. 20; 1 Cor. 3:9; 1 Pet. 2:5).

Those who are now united with Christ through the new birth (see note 2 at Jn. 3:3, p. 92) are inseparably a part of God.