Bernard Huijbers wrote a fairly fabulous book entitled "The Performing Audience," about worshipping assemblies and how the goal of musicmaking in those settings is not for the "musicians" to perform "for" the watching audience, but for all of those present to be "performing" together, for and with one another--audience as performer, performer as audience. (Gross oversimplification of a very wise book with way more content than that.)
( Click if you're curious how I will tie this to belly dance... )