In the first part of his Letter to the Ephesians, Paul spoke of the mystery hidden for centuries and now revealed: the Church, the family of God. One of the hallmarks of this body is its unity (Eph 2:11-22). But, as it is said in the second part of the letter, this unity is given in diversity: the ecclesial body has a head and members, and it must be built up and develop in a harmonious way towards fullness. In this vital process, Christ is the core topic, for he is not only the head who gives unity to the body, but he is also the giver of the gifts that allow it to develop in diversity. This subject of life is spoken of from Eph 4 onwards, vv. 1-16 being the framework in which the principles and instructions on daily life developed from v. 17 onwards are placed.

In these first verses, the letter, taking up words and ideas from other Pauline writings (1 Cor. 12; Rom. 12; Col. 2-3), introduces the whole exhortative part, insisting on the unity of believers, received as a grace (Eph. 4:1-3), and giving a series of reasons why unity must be lived and maintained (Eph. 4:4-6). With regard to the former, after the general rule ("that you walk according to the calling to which you have been called", v. 1), the concrete means for living the call are mentioned (vv. 2-3): humility, gentleness, understanding, bearing one another in love, keeping unity with the bond of peace. Certainly, unity is a gift received at the Cross, but it is also a path to be followed in daily life: it has been received and, at the same time, it must be maintained and protected, being agents of peace and reconciliation.

Vv. 4-6, already of a different tone, are composed of three series of acclamations, in which there is a progression. The first expresses that the vocation is a call to live in a single body (the Church), animated by a single Spirit (holy) and awaiting a single glory (v. 4). The second speaks of the one Lord who constituted her, of the one faith in him and of the one baptism (v. 5). The third speaks of the one God and Father of all created beings, "who is over all, acts through all and is in all" (v. 6). The logic of the progression is this: it is from the life of the ecclesial body and in living its faith in Christ the Lord that the Church can confess God as Father of all and who works in all. Or, to put it another way: it is because the Church lives, as a new humanity, what she is, that she can better understand and say how God is the Creator.

With v. 7 we begin to speak of the value of the diversity of gifts for the sake of the unity and growth of the whole body: "To each one of us [all Christians] grace has been given according to the measure of Christ's gift". 

After this advertisement, v. 8 introduces a quotation of Ps 67 (68), 19, which will serve as outline for the development of vv. 9-16: "Therefore the Scripture says: He ascended on high carrying captives and gave gifts to men". This verse, interpreted in the Jewish tradition as referring to Moses, who, having ascended to heaven, received the words of the Law to give them to men, is adapted Christologically by Paul: Christ has been exalted (Eph 1:20-22) (and has taken captive to heaven the powers that held men captive); he has given gifts (ministries and other graces); to men. The insistence is on the protagonism of Christ and on diversity in the Church:

a) vv. 9-10. Christ has not ascended to heaven like Moses, but has done so after having died (and descended to the place of the dead), definitively glorious, which will allow him to be present in all creation (like the Father in v. 6), making creation receive its full and ultimate vocation, the hope of its own glorification. The exalted Christ has the power to make his Church live and grow.

b) v. 11: "And he has appointed some as apostles, some as prophets, some as evangelists, some as pastors and teachers". The gifts that Christ gives to the Church for its proper functioning are precisely the apostles, prophets, evangelists, pastors and doctors, all of them in function of the Gospel: they proclaim it, interpret it, preach it, teach it. Christ himself gives to the Church the persons who allow her to enter into the knowledge of the mystery and to announce it. It is not the Church that gives them to herself.

c) vv. 12-16. These verses speak of the purpose of the gifts and their recipients (all believers) in two stages: growth and full stature of the ecclesial body (vv. 12-13); not to err or be deceived (v. 14) and to go all to Christ and, from Christ, to the Church (vv. 15-16). Christ has given his gifts to prepare the saints to carry out a work of service that has as its purpose the Building of the body of Christ. The end of this development is a unity that needs faith and the knowledge of the mystery (the will of God in Christ) in order to walk towards the perfect man (adult, physically and morally developed, as opposed to infantile, minor and immature), this man being the ecclesial body, which has harmoniously developed the whole of its Schools. The effects of this growth are the defense against erroneous doctrines that tempt the believers with their fallacies and with cunning that leads to error and, thanks to the realization of the truth in love, the growth and reunification with the head, Christ, which is what makes the body a harmonious and solid whole, capable of carrying out its mission statement face to humanity and the rest of creation.