“For he is our peace, the one who has made both one and breaching the dividing wall which divided — the hatred in his flesh, the law in commandments nullified — in order that the two might be created in him into one new man making peace and reconciling both in one body to God through the cross, killing the hatred in him.”
Jesus is the one who has “made both one” as well as breaching the dividing wall so that the two might be created into one new man. But who are the two being made one? In context, it is Jew and Gentile. Two groups of people who have had very separate paths — the Jews though, with the benefit of the Law (Romans 3:1-2) and all of the oracles of God. Whether they had the benefit of the divine revelation or no, both groups fell into sin and were under God’s wrath. Thus, Jesus’ death was to save both and to bind the two into one people — Jew and Gentile alike.
This is one of the errors of the dispensational system of theology. They maintain that Jew and Gentile are yet two separate peoples in the economy of God’s plan. Yet, Paul plainly teaches here that we are made one. Chrysostom makes the analogy of two statues, one silver and one lead, being melted down and recast as a single, golden statue. It is true that the Jew had the great benefit of the Word of God (hence they are the statue of silver), but they were just as lost as the gentile due to sin. Both Jew and Gentile needed the same remedy and Jesus provided that remedy to both in the same way — the cross. And now he makes his faithful into one body. The analogy is not that Jesus has multiple bodies running about, but that he has one — and that he has one bride. Will Jews be saved in abundance in latter days? Indeed, just as Paul writes in Romans 12:23-24. Yet, notice that even here, Paul speaks about the Jew needing to cease in their unbelief. They come to faith in the same way that we do — God the Father draws them to God the Son through the regenerative work of God the Holy Spirit. Was that not being done in Paul’s day? Is that not still being done today? Indeed, it is.
So the dividing wall has been broken down. Paul speaks of the hatred or enmity of the flesh and the commandments of the law being nullified. Salvation is by the grace of God given to his elect though faith. Works of the Law do not earn us merit in the eyes of God. Whether there be circumcision or no; whether there be obedience to the ceremonial law or no, those dividing walls have been broken down in the person of Christ who fulfilled the law for his own people, making us one bride and one body. How is this done? It was done through the cross whereby we were reconciled to God and our hatred of God has been brought to an end.
Hatred? Yes, hatred. Jesus says that the way we demonstrate our love for Him is through obedience (John 14:15). And so, given our disobedience, what other word but hatred is appropriate. As the Heidelberg Catechism clearly teaches, our nature is to hate God and our fellow man (Question 5). In Christ, our hatred of God is broken down and the fruit of obedience grows freely. And so, one of the marks of the Christian is faithful obedience to God (or at least an attempt at it). Those who refuse to repent of their sins and obey the Word of God betray their unregenerate hearts.