My dictionary defines a community as:
1. a) all the people living in a particular district, city, etc. b) the district, city, etc. where they live 2. a group of people living together as a smaller social unit within a larger one, and having interests, work, etc. in common
Community has a strong sense of place of people living together. This comes from the words Latin root, the verb communire, which means to fortify thoroughly on all sides.
A good example of community in this sense is a group of people living in a walled village, banded together in defense against a common enemy or threat.
More positively, a community may be a group of people who have so much in common that they want to be identified as such and distinguished from others.
Such like-minded people dont have to be living in the same place or physically banded together. With the rapid advance of communications, the element of place geography is no longer important.
If you take geography away from the meaning of community, you have a group of people [functioning] together as a smaller social unit within a larger one, and having interests, work, etc. in common.
The best word to describe that kind of community is network.
Going back to the dictionary again, a network is 1. any arrangement or fabric of parallel wires, threads, etc. crossed at regular intervals by others fastened to them so as to leave open spaces; netting; mesh 2. a thing resembling this in some way; specifically a group, system, etc. of interconnected or cooperating individuals.
The church has both kinds of communities communities linked to place and communities as networks.
For example, there have always been territorial parishes (parishes defined by a geographic area) and personal parishes (parishes for certain groups of people with the same language, nationality, etc.). In practice, more and more people act as though their parish community is a network rather than a geographical area.
Authority can be exercised in both senses as well. For example, three patriarchs live in Damascus Greek Orthodox, Melkite Greek Catholic and Syriac Orthodox. Each is titled Patriarch of Antioch, but they are spiritual leaders of separate networks of Christians, not of all the Christians who live in the one place.
Religious communities have always been considered groups of people united by a common spirituality and tasks, even though they may be scattered all about.
Actually, a good model for the whole church is that of a network, even a network of networks. From this point of view, Christian unity is all about building interconnections and cooperation.
This is almost the way church unity was described in the early centuries. Unity was considered to exist if there was peace and communion among the churches.
Banded together behind common walls doesnt make for unity, but functioning together in the Spirit of the Lord does.
Msgr. Archimandrite Robert L. Stern