Remember (11): Our new life in Christ has implications beyond our personal repentance and sanctification. We are to live as the united church of God, no matter our background. But it was not always like this. Prior to the cross, we Gentiles faced an insurmountable barrier to the people of God (the Jews), who alone had access to the only true God. They saw us as the "Uncircumcision." And since we were cut off from them, we were also cut off from the holy God whom they were to worship. And we are to humbly remember that this was our prior condition. We were not the people of God. We had no access to Him.
Without Christ (12): This was all because we were "without Christ." Apart from Him, we were non-citizens, outside "the commonwealth of Israel". This meant exclusion from their national blessings like the millennial kingdom. This also meant we (and our forefathers!) had no access to the covenants of Abraham, David or the New (not even the knowledge of them!). Moreover, we had no hope—no hope of atonement, justification, resurrection, kingdom of God, glorification, etc. Finally, and most tragically, without Christ, we were all (whether atheists or vain idolaters) "without God in the world." How pitiful was our condition without Christ! But in Him and in His blood (2:13), all this totally changed! In His cross, we became one—the church of God (2:14-16).
 "Therefore" (2:11) introduces the corporate side of being "His workmanship" (2:10). Cf. 2:19-22.
 Inaccessibility to God is the main issue here (2:12, "without God in the world"). This is resolved in 2:16-18.
 Paul elsewhere warns against Gentile arrogance. Cf. Rom. 11:17-18.
 NASB's "separate" is literally "without [chō-ris (χωρίς)]." What follows this phrase are all appositional.
 "Commonwealth [po-li-tei-a (πολιτεία)]" refers to citizenship. This idea is brought up again in 2:19 ("fellow citizens [sum-po-li-tēs (συμπολίτης)] with the saints") where we are seen as citizens in Christ.
 Examples include Christ's righteous reign, non-violent animals, wealth, safety, etc. (Isaiah 11:3-9; 60:17-18).
 Idolatry is vain. Cf. 1 Kings 18:29 and Isaiah 44:16-17.