Eph. 4:12 equip. This refers to restoring something to its original condition, or its being made fit or complete. In this context, it refers to leading Christians from sin to obedience. Scripture is the key to this process (see notes on 2 Tim. 3:16–17; cf. John 15:3). saints. All who believe in Jesus Christ. See note on Eph. 1:1. the work of ministry. The spiritual service required of every Christian, not just of church leaders (cf. 1 Cor. 15:58). building up of the body of Christ. The spiritual edification, nurturing, and development of the church (cf. Acts 20:32).

Eph. 4:13 unity of the faith. Faith here refers to the body of revealed truth that constitutes Christian teaching, particularly featuring the complete content of the gospel. Oneness and harmony among believers is possible only when it is built on the foundation of sound doctrine. the knowledge of the Son of God. This does not refer to salvation knowledge but to the deep knowledge of Christ that a believer comes to have through prayer, faithful study of his word, and obedience to his commands (cf. Phil. 3:8–10; 12; Col. 1:9–10; 2:2; see note on 1 John 2:12–14). the fullness of Christ. God wants every believer to manifest the qualities of his Son, who is himself the standard for their spiritual maturity and perfection. See notes on Rom. 8:29; 2 Cor. 3:18; Col. 1:28–29.

Eph. 4:14 carried about by every wind of doctrine. Spiritually immature believers who are not grounded in the knowledge of Christ through God’s word are inclined to uncritically accept every sort of beguiling doctrinal error and fallacious interpretation of Scripture promulgated by deceitful, false teachers in the church. They must learn discernment (1 Thess. 5:21–22). See Eph. 3:1; 4:20.