Ecclesiology—the doctrine of the church—occupied much of the Reformers’ attention because the Reformers loved Christ and His Word. They wanted to be faithful to their Savior, and they recognized that they could not be faithful unless they carefully studied the Scripture and thoughtfully applied its teaching on the nature and practice of the church so that the covenant community would honor Jesus. Christ loves His church, which is His body (Eph. 5:25–33), so the doctrine of the church must be taken seriously.
During the Reformation, the Protestants and Roman Catholics argued strongly over the identity of the head of the church. Although the Roman Catholics did confess, at least nominally, that Christ is the head of the church, they had in effect supplanted His headship with the headship of the pope. For the Roman Catholic Church taught then and continues to teach today that the pope is the earthly head of the church. As a consequence of that teaching, the pope is invested in Roman doctrine with powers, honors, and other benefits that rival those of Christ Himself.
However, the Apostles identify only one head of the church, namely, Jesus Christ. A body has only one head, and Paul in today’s passage states explicitly that Jesus is this head (Col. 1:18). Our Lord does appoint pastors and elders as undershepherds who help lead and guard His body during its earthly pilgrimage (1 Peter 5:1–5). These men have true authority in the church, but they are not the church’s head. They do not have by virtue of their office the gift of infallibility when they teach, nor are they kings who are not accountable to the church or to Christ. Because no single pastor or elder is the head of the church and because a group of pastors and elders do not constitute the head of the church, the only authority that these men have is declarative. They may only declare to God’s people what Christ has already spoken in His Word, and their teaching has authority only insofar as it conforms to the prophetic and Apostolic tradition—sacred Scripture.
Because Christ is head of the church, He not only has final authority over the church but He gives life to the church. John Calvin comments that as head of the church, Jesus is the “root, from which vital energy is diffused through all the members, so the life of the Church flows out from Christ.” The church finds her life in Jesus Christ our Lord.