1 Corinthians 12:12-27
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 sense of hearing? If the whole body were an ear, where would be the sense of smell? But as it is, God arranged the members in the body, each one of them, as he chose. If all were a single member, 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.” On the contrary, the parts of the body that seem to be weaker are indispensable, and on those parts of the body that we think less honorable we bestow the greater honor, and our unpresentable parts are treated with greater modesty, which our more presentable parts do not require. But God has so composed the body, giving greater honor to the part that lacked it, that there may be no division in the body, but that the members may have the same care for one another. 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.
So, what exactly makes a church more than just a group of people who have something in common? Anyone who has seen the Tom Hanks production of Band of Brothers could well say that there's nothing supernatural about the kind of relationships that going to war together develops. The men who lived through the siege of Bastogne together didn't survive because they had all somehow been thrown into the same hell together on December 20, 1944. They didn't even learn to survive together over the course of the seven days frigid days they were there. Those men survived together because they had been trained to it, some of them through more than two years of engagements together living day in and day out in all kinds of conditions.
To listen to the banter between the men in Hanks' dramatic retelling of the community that was the 101st Airborne it is clear that these men didn't always like each other. They sometimes fought quite fiercely among themselves. But they never abandoned one another. If they did, they paid for it; often with their lives.
There are a lot of groups of people inhabiting church buildings, rental halls, and even home fellowships together today. The important distinction between the inhabiters who are just a group of people who meet every Sunday and a true church is that the true churches are ones where the people fight with each other for each other and refuse to let go of one another because they have lived "life together," as Bonhoeffer put it. Churches, just like platoons, often fall apart in that critical stage where they have not yet learned to trust one another through the testing of life together. You can put a veneer on if you only see a person on Sunday each week and for the occasional meeting or church fair. But that veneer won't last beyond the first time that your fellow member crosses you or wants something you don't want.
The drill sergeants who trained the 101st Airborne by making them run up a mountain over and over again in the sun, in the rain, after a large meal, when they didn't feel like it, in the early morning and late at night knew what it takes to turn a bunch of guys into a Body: repeated experience, work, and perseverance. Community begins with a group meeting and eating. Worship and Sacrament are a great start. But it takes going out on the road together to share Christ or committing to working a mission or soup kitchen together over a long period of time before you have a real Body. That's part of why Jesus sent the disciples out on a preaching and healing mission mid-ministry. People who have committed to one another, not just by reading a covenant or creed that they all believe in, but by living a covenant with one another and by being a creed to one another really have something. They have become members of one another.
The men of the 101st Airborne wore that name proudly then and long after the war. Do we who wear the name of Christ own one another like arms or legs? And do we own the weaker members; the ones with troubles and incapacities that make them difficult to endure? If we do, we're really got a great start on building a fighting unit. Rather than going to war with each other, will we be willing to go to war with each other? Only when our faces are set toward the same goal and the same purpose will we fight alongside one another and not just fight one another.