Paul refers to an illustration that he uses several times in his writings, that of the church as a body. When we think of a body, we think of its members functioning together simultaneously. The members are not the same, yet each is essential in order for the body to function properly. The same is true of the church. To the extent that one member does not function as he or she should, the church is hindered, which makes very serious the failure to function in the particular way God intended.
Some people have in a humorous way, depicted what happens when a church does not behave like a body. They do so by using other illustrations and here are two of them. One illustration is that the church is like a bus: the minister is the driver and the members are the passengers. They drive to all kinds of interesting places, enjoy each other’s company, but they don’t make contact with people not on the bus. Sometimes it stops at a bus stop, but no effort is made by the driver or the passengers to invite others on board.
Another illustration is that of an aeroplane. The minister is the pilot, the crew are the staff, and the members are the passengers. The plane takes off and climbs out of sight of people on the ground. Eventually the plane is put on automatic pilot and people snooze away the time on the flight or else read something. It arrives at its destination with the same number of people as when it started.
The point that those humorous illustrations stress is that only a few people are doing anything whereas the imagery of the body requires everyone to do something, and the something each does is their gift, whatever it is.
Paul mentions that the illustration of a body reveals that a church is composed of persons united to one another. The illustrations of a bus and a plane gave to each person a separate seat as it were whereas the illustration of a body stresses the necessity for each person to do his part. On the bus and the plane, it all depends on one individual – the driver or the pilot – fulfilling his role. In the illustration of the body, it depends on all of them doing so.