Adam Clarke's Commentary on the Bible

Verse 12 (Ephesians 4:12)

For the perfecting of the saints - For the complete instruction, purification, and union of all who have believed in Christ Jesus, both Jews and Gentiles. For the meaning of καταρτισμος , perfecting, see the note on 2 Corinthians 13:9 .

For the work of the ministry - All these various officers, and the gifts and graces conferred upon them, were judged necessary, by the great Head of the Church, for its full instruction in the important doctrines of Christianity. The same officers and gifts are still necessary, and God gives them; but they do not know their places. In most Christian Churches there appears to be but one office, that of preacher; and one gift, that by which he professes to preach. The apostles, prophets, evangelists, pastors, and teachers, are all compounded in the class preachers; and many, to whom God has given nothing but the gift of exhortation, take texts to explain them; and thus lose their time, and mar their ministry.

Edifying of the body - The body of Christ is his Church, see Ephesians 2:20 , etc.; and its edification consists in its thorough instruction in Divine things, and its being filled with faith and holiness.

- Adam Clarke's Commentary on the Bible