We seem to spend a lot of energy trying to start new small congregations, of 20 to 30 or so people.

If this can be done en masse, praise God. However, there are substantial difficulties in doing so.

First, there are financial barriers (they will generally require sustained investment). Second, there is a high degree of intensity and commitment required on the part of a small number of people. Just to get a regular Sunday meeting running means that most of the congregation will need to be on a roster of some kind more weeks than not.

Over time, at least some (if not most) of the Gospel-hearted servants who started the exciting endeavour become tired. I meet a steady trickle of people from such situations who are just looking for a break. The initial energy and enthusiasm for evangelism ends up being directed toward enabling a structure to run, and in turn some end up getting burnt out.

Optimal rather than viable

So often the question driving the start of such good endeavours is the question of viability.

However, I have recently heard a couple of different people suggest that the optimal church size (from a growth perspective) is between 50 and 150 people. I am not sure whether there is research behind this assertion, or if it is more of a gut feel.

Either way, these comments have got me thinking: what is the optimal size of the launch group when starting a new congregation. If it is true that the optimal size of any church is over 50 and under 150, why don't we focus our energy on helping congregations in the 120-150 range work out how to split into two evenly sized new churches?

Not only would such an approach avoid the financial barriers to church planting (it is far easier for a group of this size to fund a new minister), but the economies of scale make it more likely that the work required to start something new is spread over more people.

Well, this is just a random thought. Perhaps I have missed something important?