Attaining to mature manhood the accomplishment of combining two groups into one “new man,” so making peace (cf. Eph 2:14-18).
If it is correct to understand this description to refer to individual maturity, it would clearly seem insurmountable and unreachable in this life and must refer to the “end of time” when we are made perfect. However, Paul is speaking of the body of Christ as a whole, instead of individual growth. Campbell suggests that it’s both because you can’t separate the body from the members of the body. He writes, “ It has been questioned whether he is speaking of the perfect character of each individual or of the church as a whole. But the inquiry is useless, for the two things are necessarily conjoined, and in their actual attainment form one. The perfection of the whole body implies that of each member; and, as the number of such members increases, the growth of the body advances towards perfection.” No one denies that the body is made up of members, but they are not the same, and the maturity of one does not necessarily infer maturity in the other. Connected with the body is the development of a people from two very segregated peoples – the Jews and the Gentiles. Ephesians 2:13-19 reads,
But now in Christ Jesus you who once were far off have been brought near by the blood of Christ. For he himself is our peace, who has made us both one and has broken down in his flesh the dividing wall of hostility by abolishing the law of commandments expressed in ordinances, that he might create in himself one new man in place of the two, so making peace, and might reconcile us both to God in one body through the cross, thereby killing the hostility. And he came and preached peace to you who were far off and peace to those who were near. For through him we both have access in one Spirit to the Father. So then you are no longer strangers and aliens, but you are fellow citizens with the saints and members of the household of God.
The mystery that had been hidden is that the “Gentiles are fellow heirs, members of the same body, and partakers of the promise in Christ Jesus through the gospel” (Eph. 2:6). The New Testament acknowledges this tension between Jews and Gentiles. Even though the truth of the gospel was revealed as early as the baptism of Cornelius and his household (recorded in Acts 10), its acceptance was not fully realized until years later. Even Paul and Barnabas are carried away by the influence of their Jewish brothers (Gal. 2:11-14). The Jerusalem Conference, recorded in Acts 15, was designed to confirm that all the inspired men are united in their message that Gentiles are also recipients of the gospel. James advises Paul in Jerusalem to seek peace with the Jews (Acts 21:17-24), who think he’s teaching against their way of life and the law of Moses. This tension is an ongoing problem in the early days of the disciples. Building this bridge did not occur overnight. This body was slowing maturing to include one new man, a man that is a combination of both Jew and Gentile into one body. This was accomplished in that generation.