For just as the body is one and has many members, and all the members of the body, though many, are one body, so it is with Christ. For by one Spirit we were all baptized into one body—Jews or Greeks, slaves or free—and all were made to drink of one Spirit. For the body does not consist of one member but of many.
If the foot should say, “Because I am not a hand, I do not belong to the body,” that would not make it any less a part of the body. And if the ear should say, “Because I am not an eye, I do not belong to the body,” that would not make it any less a part of the body. If the whole body were an eye, where would be the hearing? If the whole body were an ear, where would be the sense of smell? But as it is, God arranged the organs in the body, each one of them, as he chose. If all were a single organ, where would the body be? As it is, there are many parts, yet one body. The eye cannot say to the hand, “I have no need of you,” nor again the head to the feet, “I have no need of you.” . . . If one member suffers, all suffer together; if one member is honored, all rejoice together. Now you are the body of Christ and individually members of it. (1 Corinthians 12:12-27)
Peter Kreeft comments on being a Christian and a member of the Body of Christ, the Church:
“I am I whether or not I am a part of a party, a club or a nation.
But this is not true of members (organs) in a body. Remove heart, lungs or kidneys from the body and they die.
A member of a group has a life outside the group; an organ in a body has no life outside the body. An eye removed from the body and put on a plate no longer lives. It is even no longer an eye. It cannot see outside the body, it loses its identity.
This is how we are related to the Church. The Church is not essentially an organization but an organism. The Church is not Christ’s society but Christ’s Body.
The Christian has no life or identity apart from Christ (and therefore apart from his Body). If I were to die and discover that there was no Christ, that Christ was dead, that Christ was not God, that I was not alive with his life in his Body, then I would not be I, I would be another person.
(Christianity for Modern Pagans, p. 319-320)
Most interesting insight into being a member of the Church – “The Church is not Christ’s society but Christ’s Body.” Each member is indispensable to the Body, and no Christian can claim that he or she does not need the Body of Christ. The Body is essential to the life of each Christian who can remain alive only as part of the Body.