In short, I think if we want to get a more accurate picture of the church in a complex society, we need to look at the church gathered and scattered, the congregation and the aggregation.
The congregation is the regular gathering that is often weekly. A lot of new believers gather in a weekly event with the same believers each week in the same place. This is normal in a simple society.
The aggregation is the seasonal or irregular gatherings that may be yearly or just a spontaneous gathering. In a complex society with modular expressions of church, or a transitional society with high mobility, those on pilgrimage or in the underground church, the aggregation might be a more accurate way to measure growth.
Our meetings have finished up and my mission geek friends have flown off to their respective countries. Except for Andreas and Christine Wolf (researchers) who will spend 2 more days with us here.
One of the things we discussed was the difficulty in tracking church planting movements in a complex society. In a simple and singular world (villages in rural China) you can just measure how many churches are started and how many people are involved in them - and of course watch their transformational impact on the various layers of society (judicial, edcutational, arts, etc)
But what if new believers decide not to attend a Sunday service type church but rather choose a more organic and underground expression - decentralized, based around homes and special events, city-wide events, festivals, - what if they did not join a single cell church but rather morphed into the region-wide multiplicity of believers as living stones in an invisible building?
I threw out a suggestion - we should measure aggregation as well as congregation.
Congregation - weekly, permanent, visible, tied to building, denomination based
Aggregation - spontaneous, yearly, beyond the denomination,
just a thought . . .