Christ the Head, is the seat of all authority for the church. The analogy of the church and the human body is very close. While the body is one and the church is one, both are made up of various members, each having his own gifts and temperaments. Although there is a great diversity of gifts, that does not preclude harmonious association and operation. In fact, the members can perform their proper functions only when they do work together.
Fulness.
Gr. plērōma, “full number,”“full extent,”“entire contents”; also “complement.” The word refers to that which is filled (passive sense), or to the filled condition of a thing (cf. on Col. 1:19). Paul sees the church as the body of Christ filled with the fullness of God (Eph. 3:19). Christ has poured His fullness, His qualities, into the church, filling it with holy life; indeed, with abounding life. In Colossians, Paul emphasizes the deity of the Head, in Ephesians the privileges of the body.