THE British anthropologist and Oxford professor Robin Dunbar has posed a theory that the number of individuals with whom a stable interpersonal relationship can be maintained (read: friends) is limited by the size of the human brain, specifically the neocortex. “Dunbar’s number,” as this hypothesis has become known, is 150.
Perhaps this is why the Alban Institute set the number of worship attenders at 50 – 150 for a pastor size congregation. A pastor can only maintain so many relationships. I rarely see a pastor sized congregation grow beyond 200 in worship, and that takes a uniquely gifted pastor.
I’ve been musing about this number relative to the former “rule of 100′s” as well. It used to be said you needed a budget of $100,000 and a worship average of 100 to sustain a full-time pastoral sized church. Now I’ve heard that rule is the rule of 125. I strikes me that there is a pretty slim margin then between 125 at worship and the 150 “cap” congregations often find ways to self-recalibrate toward in maintaining this style of ministry and incorporation.