More on the New Testament Church

I want to reflect upon two parts of the discussion today.
1) What does a New Testament Church do?
2) If we could only do one thing in this area, what would it be?

These two questions I think, are a part of the key of how the church approaches the world. If we focus upon the particular activities of the early church we are going to get into debates about communal living and what is or isn't a contemporary idol. While some of that conversation could be helpful and meaningful it would most likely be the points of contention rather than focusing upon the many other things that the church did such as worship, pray, etc.
There is a common theme in the Bible in both the Hebrew scriptures (Old Testament) as well as the Greek scriptures (New Testament) that following God and being apart of God's people means caring for the widows and orphans, the foreigners among us, those who are lonely and ill. These are not New Testament activities they are God honoring activities. The difference in the New Testament is Jesus. Jesus makes a relationship with God possible because those who accept the grace/forgiveness of Jesus are able to enter into the presence of God for eternity as well as have the presence of God/Jesus in the form of the Holy Spirit here and now.
Without getting into a long theological/theoretical discussion the difference between the New Testament and the Old Testament is Jesus. The expected activity of the church is not really any different than what runs through the entire Old Testament. (There is a reason why we quote from the OT prophet Malachi, "Do justice, love mercy,and walk humbly with your God" as an emphasis upon what our lives of faith should look like.)
So what does the NT church do? It focuses on Jesus! It looks first to Jesus in all things, it reflects the forgiveness given by Jesus, it suffers on behalf of others, it stands against injustice, it proclaims that today is God's day and we will live in the midst of it. It does not so much do things as it reflects the image of Christ. In several places the church in the NT is referenced as the Bride of Christ. A bride is a bride not because she is going to cook or clean or doing wifely things, all these things can be done by people who are hired for the job. The difference is that a bride has a relationship with the groom that is to be like none other. So the church is to be in relationship with Jesus.
To make a long rambling a bit shorter I think this is the key, the church is to be in an active relationship with Jesus just as a bride would be with a groom. It doesn't mean doing things to earn his love, but rather to be in a relationship where love is growing each and every day.
Because of this answer I can only say that the one thing we can do in this area is to love Jesus. Anything good will only come from that reality. Love Jesus and make it our only priority.