The word congregation, like assembly, is another legitimate translation of ecclesia, which is used in Scripture to refer to the “church” in a home, in a city, in a region and even in the whole world. In this sense, every jurisdiction of Basileia is a congregation. And while it is tempting to refer to a Fellowship as a local congregation, the word “local” is problematic in a day when many people are intimately, genuinely and constantly connected in virtual ways that are anything but “local” in a geographic sense. Thus we don’t use the word congregation in any definite way, but employ it only as a synonym of assembly or ecclesia.
Also see Church, and Jurisdiction.