What is the Church of Christ?
The church is the people. It is the total of all people who obey Christ, who unreservedly commit themselves to Him, who find peace and joy in His service.
Christ and the church are inseparable. Christ gave Himself for the church, purchasing it with His blood.
What is the church like? It is like a human body. The head supplies the body with its life. The head directs the body. The head saves the body from harm. The head unifies and coordinates the different organs of the body. But at the same time, the head depends upon the body to carry out its functions.
In like manner, Christ is the head of the church, which is His body. Christ gives life to the church. Christ guides and controls the church. Christ is the savior of the church. In Christ, the church--composed of people who differ in race, background, culture, status, and talent - is one. Yet, Christ, the head, depends upon the church, the body, to accomplish His purposes.
The church is the hands, feet, and mouth by which Christ works and speaks within the world.
It is therefore impossible to understand the church without affirming that the church, as the body, and Christ, is the head, are inseparable. This understanding of the Church as the body of Christ points out the necessity of being a member of that body.
Any individual who is not a member of the church is not in the body of Christ. This is the doctrine of the New Testament.