Why is the church important? (A note on the eschatological roots of Christianity)

A friend of mine who serves in a ministerial position prompted me with the question, “Why is the church important?” Obviously this is a very broad and opened ended question, without parameters—other than knowing his purpose was to teach young people in a retreat setting. However, rather than go through a whole proper prolegomena, I tried to say in brief why the church is important from my theological perspective. Here is what I said, with minor editing changes:

The church is important because it is part of God’s work to save all of creation. Part of the good news Christianity has to share (“gospel”) is that God reconciles not only God to humans, but also humans to humans. Sin has divided us from God, but also from each other. Therefore we are being reconciled to God, and to each other, and the church, being a foretaste of the Kingdom of God, lives into the reality of this future (in the Kingdom) by living a common life, which happens to be structured around a common meal. In this common meal, fellowship is a result of and a spur for reconciliation, as we all become one loaf of bread together (mixing metaphor and description here). So the church is the bearer of a message, but also is part of the message itself; that is why it is important.

What is important within the context of me posting it here  (but was not so important for responding to my friend’s prompt) is what I don’t say. I said nothing about the church’s relationship to Israel, or extra eclessiam nulla salus, or even that the church is necessary for salvation (I might say the church is salvation, but I would then look at salvation to see the church, not the other way around). At any rate, there is a lot I could intentionally not say (and maybe discussion will bring it up), but I wanted to throw out an experimental thought. I should think it through more thoroughly before I say it with much confidence, but I think I want to say this: the church receives itself from the future (choice of noun is difficult here, because I don’t want to say the church has a “self,” yet I do want to affirm that the church is somehow the “body” of the “Christ”). If the church is constituted by the Holy Spirit (as is traditionally held, referring to Pentecost as the “official” birth of the ecclesia), and if the Holy Spirit brings the future, then the church is created from the future, not from the past, and can stand on no historical foundation to guarantee its self-authenticity. This may not seem unique or controversial (I’m going for neither effect), but it leaves me to think differently about the Jewish “roots” of Christianity, and the relation of the church to Israel. Should we rather speak of the eschatological roots of Christianity (while holding on to the idea of Gentiles being grafted into Israel)? I think this is the direction I need to think, as I consider the relation of the church to her mission, and her relation to God’s elect people of Israel. This means I will need to consider more thoroughly the relation of promise and fulfillment between the Hebrew Scriptures and the New Testament, as well as what it means for the church to be secure only from a future that has yet to arrive in full, lacking any history that can generate her authentic reality.