I was listening to a CD series yesterday (CD #15 ). The speaker made a very good point, I think. I won't burden you with the greek words, but this is the giest of what he had to say.
The NT writers actually had a choice when it came to using a particular word to reference the church.
There was a word that spoke of a group of people assembled to serve a particular god. There was another word to describe a group gathered to consider the various concepts relating to a diety. There was a third word with some kind of religious connotation and then, there was this word ekklesia from which we have our word "church." The gk word describes a secular or community meeting of citizens for some kind of public good. As we view the didache of Christ against the back drop of benevolent ministry -- spiritual teachings, if you will, tied to a social concern , we can understand how it is that the word for a meeting of the community was used instead of some "religious " word.
JD