Paul has been explaining this wonderful calling we have as God’s People, and how that drives him to pray for the church. Now he calls them live lives worthy of their calling (v.1), to be what we are in Christ. The ultimate plan of God is to unite all things under Christ (1:10), and that plan is being worked out now in the church, the new humanity, and so a crucial aspect of being what we are is living out the unity that is ours in Christ, and realising that unity more and more. That’s the theme of these verses.
Notice that in these verses unity is a given, it is something to be maintained not manufactured (so “keep the unity of the Spirit”, v.3). It’s a unity grounded in the unity of the Godhead – one Spirit animates the one Body, one Lord (ie Jesus) to whom we are all united through baptism, one Father and therefore as church we are one family. But just as a human family is a unit, but in a dysfunctional that unity is far from evident, so we need to be careful (“make every effort”) to guard and live out that unity. To that end the commands in verse 2 are crucial: we need the humility that puts others needs before our own, the gentleness that doesn’t insist on our own rights, the patience and forbearance and love that will not let grievances drive us apart.
In these verses unity is not so much a treasure to be guarded as a goal to be reached (so v.13). Christ enables this growing unity, wonderfully, through diversity – giving to each of his people gifts. “Grace” in verse 7 speaks not the saving grace which every Christian knows in equal measure in Christ, but the gifts which he distributes to each Christian variously for ministry. I wouldn’t get too bogged down in vv. 9-10, Paul’s point is simply to show how he sees the Psalm fulfilled in Christ, who now as the ascended Lord, distributes gifts to all his people as evidence of the victory he has won.
In verse 11 he mentions just some of these gifts, though we will see they have a crucial role. The “apostles and prophets” are foundational gifts (cf. 2:20 – whilst I think there is a form of prophecy that has an ongoing expression in the church, here he seems to be referring to, not Old Testament prophecy, but a foundational gift of authoritative teaching (so 3:5) which we have preserved in the New Testament. Evangelists are those who speak God’s word to those outside the church, pastor-teachers are those who speak to those within the church. All are word ministry gifts. They have a particular importance but notice their purpose (v.12): to equip all God’s people to use their particular gifts, serving in various ways. The body will not grow to maturity if we put a full stop at the end of v.11 and suppose it is sufficient that the church is fed well through good teaching. No, the church will only grow to maturity as we each learn to play our part and serve one another; and we need the Bible and people who can teach it to us so that we can be equipped to do so.
The maturity we seek is characterized by knowledge of Christ and likeness to Christ (so vv.13,15), and to grow in this maturity we need both truth and love. Truth so that we have a firm grasp of the faith and aren’t “blown here and there” by false teaching; we must each learn to speak this truth to one another to build one another up. But we must do so “in love”, love that expresses itself in sacrificial service “as each part does its work” (v.16).