What is the Church for?

I had a very interesting conversation this past weekend. A friend of mine is going through a transition in his church, and so he is asking some basic questions about the Church. And you can't get more basic than what is the Church for?

I guess before you can ask what is the Church for you have to ask what is the Church. I think, simply put, the Church is the people of God. The earthly manifestion of the Body of Christ. Now for the hard part -- What does that mean? It's kinda hard to get your head wrapped around a concept like the "Body of Christ" or "the People of God." You know Israel was chosen by God and they didn't fair to well. Kinda makes you think what's instore for us modern folk?

After you figure out the primary function, purpose and goal of the Church, then hard part starts. You have to figure out your part in the Church! And that means serious self-examination, and then some serious action. Now that is the real 'existential' dilemma of our existences. If we really existence as the people of God, then what is our purpose in fulfilling our existence?