This passage forms the hinge between the theological statement of Ephesians 1-3 and the exhortatory material that follows (4:17-6:20).
It provides a theological rationale for the behavior that is required of the church.
The primary call is to unity. The recipients of the letter should make "every effort to maintain the unity of the Spirit in the bond of peace" (4:3). They are to equip the saints for ministry "until all of us come to the unity of faith and of the knowledge of the Son of God" (4:13). The sevenfold use of the word "one" (4:4-6) forms the center of a poetic statement of the church's unity. The list culminates with the oneness of God. Just as earlier parts of Ephesians have identified God as the source of the church's identity (cf. 1:3-8), so here the unity of the church reflects the oneness of God.
In the Greek, verse 7 also begins with the word "one." In English translation, it is not possible to maintain the parallel. "And each one of us was given grace" is one way to think of the parallel made by the Greek. Following on the heels of verses 4-6, verse 7 brings the notion of oneness back to the individual experience--each one of us. The believer's experience of God's grace relates to the larger goal of the oneness of the body.
The unity of the church is a reflection of God's gift of reconciliation in Christ. The opening "therefore" (4:1) indicates that the argument here follows logically upon the previous verses. In Ephesians 1-3, the author has elaborated upon the reconciliation between Jews and Gentiles that God has brought about in Christ. The repeated use of the word "one" in 2:14-16 (as in 4:4-8) highlights this aspect of the message: the church is "one new humanity" created by Christ. The mystery of the faith (cf. 3:9) is that, through the one body of Jesus, God has brought together two disparate groups under one plan of salvation. While both Jews and Gentiles once lived according to the flesh (2:3), Jews were nevertheless "near" to God, while Gentiles were "far off" (2:17). Through Christ, both groups are now joined together and draw nearer to God. The writer uses two metaphors to express the joining and the resulting closeness with God: Jews and Gentiles form one body with Christ as its head (1:22-23), and one structure with Christ as its cornerstone (2:21-22).
The church should reflect this unity. However, the author makes clear that the perfection of the church is a process and not a completed event. Christ has equipped the church with gifts (4:7, 11) so that the church as Christ's body may reach maturity. The body metaphor of verses 12-16 is interesting: the church is depicted as growing into its own body. Christ is already "mature" (verse 13; the Greek that the NRSV translates as "maturity" is more literally "the complete man"). Yet the church, which is Christ's body, must build up the body until it arrives at the stature of Christ (verse 13). Likewise, in verses 14-15 the image evoked is that of the body growing up to meet its head, Christ. In the author's view, the church is already the body of Christ, even as it continues to grow toward Christ.
The list of offices in 4:11-13 poses a theological problem for many interpreters. In these verses, the gifts given by Christ appear to be identified with various leaders, whose job it is to train all the saints. By contrast, the "gifts of the Spirit" of which Paul speaks of in 1 Corinthians 12 seem to be gifts that any believer may possess and use for the good of the body (cf. 1 Corinthians 12:4-11). For many readers, the related text in 1 Corinthians may be more appealing because the whole church shares equally in the gifts of God. Here, the gifts seem to belong exclusively to church leaders--or, more precisely, the gifts are the church leaders.
However, it is also possible to read 4:11-13 as a recognition that good leaders are necessary for the church's unity. Elsewhere, the author has already assumed that God has given grace as a gift to every believer (4:7; cf. 1:3-6). Nevertheless, certain people are gifted in particular ways for the building up of the body, and this is a gift of God's grace. The language here does not demand uncritical obedience to leaders, but understands leaders as a gift from God to guide the growth of the body.
Seen in the context of Ephesians, the unity to which the church is called in 4:1-16 can have challenging implications for contemporary churches. In the first century, many Jews and Gentiles struggled to accept the message of reconciliation of Jews and Gentiles (cf. Galatians, Acts 10-15). God's gift of reconciliation means that those who were understood to be "far off" are now those who are equally gifted by God. The "dividing walls" of today's churches might also be seen in this light, although in our case the more relevant categories would be those of gay and straight, black and white, rich and poor, or men and women. In its unity the church should embody the reconciliation made possible in Christ, who "has broken down the dividing wall, that is, the hostility between us" (2:14).
In Ephesians, unity is not the same as uniformity. The mystery of God that is revealed in Christ and results in the reconciliation of Jews and Gentiles does not obliterate the distinctions between these different groups. Instead, what is made known through the church is "the wisdom of God in its rich variety" (3:10). Part of the call of 4:1-16 is to tolerance, or "bearing with one another" (4:2). The assumption is not that all distinctions will cease, but that even with the persistence of differences, the church may nevertheless grow together as a body.