I’m on the record at various places on this blog as warning about future hiccups in Church growth. Medium-term, I think we need to reconcile ourselves to a world where the center of traditional Church strength enters a period of no or negative growth for the foreseeable future. Additionally, as developing countries become developed countries the higher levels of growth in other areas of the world will taper off as well. (However, a few months ago I was on the record as predicting that Church growth would be under 1% this year, and I was wrong).
However, for various reasons I’m optimistic about Church growth in the long-run. I’ve alluded to this elsewhere, but if your belief system thrives in places that are thriving and reproducing, and is in a decline in places that are in decline, then the fundamentals are strong even if the Church may ebb and flow temporarily throughout time and space.
When people are promoting a particular worldview or ideology, one seemingly random question I ask in the back of my head is what the birthrate of that ideology’s community is. If it is not at or above replacement, then in addition to not fulfilling the most basic reproductive imperative it’s also a non-starter in terms of whether it’s fundamentally viable. It can survive or even flourish, but its continued existence is a testament to the intrinsic, existential contradiction that its own survival is dependent on the people essentially created by competing ideological systems.
The fertility differential between conservative believers and others are so stark it sometimes seems like the only ones who will be around in the next generation are RadTrad Catholics or Hutterites. As an overly simplistic back-of-the-envelope exercise, there are some religious groups that seem more resistant to the demographic transition forces that are fun to speculate about. For example, the Amish have a doubling time of 20 years. (It’s numbers like this that led to a small band of religious exiles from Illinois becoming 1% of the US population in 150 years). There are about 350,000 Amish; at that rate then in 100 years there will be about as many Amish then as there are Pennsylvanians now, and then 100 years after that there will be more Amish than there are Americans now.
Of course 200 years is a long time for something to happen or things to change so I am not making the claim that in 200 years half of the US will be agrarian Anabaptists. Still, it shows the power of growth in highly religious subcultures, and there’s a good case to be made that differentials like this is how Christianity took over the Roman empire in 300 years. (Of course, we don’t enjoy such rates, but comparing those rates to virtually any group that is less traditional in their orientation mitigates against the idea that loosening up or liberalizing will help Church growth, even in the developed world.)
Of course, there is a question whether the family size difference will be enough to swim uphill against particular ideological and social trends working against religious devotion, but such pressures ebb and flow in the long run, but religious/traditional people having more babies has been a pretty consistent given since reliable family planning became a thing, and once people opt out of religion they become part of a community that isn’t replacing itself. Headwinds come and go, but the fundamental forces grind on.
While you have to be careful when going in this direction, I’m even open to there being a genetic component to all of this: as religiosity has been shown to have a genetic component, and religious people have more children (and generally live longer), then over time things like belief in God that I suspect has a visceral, almost biological component will increase. (I published a speculative paper on the math involved with larger families begetting more large families and what it means evolutionarily).
Additionally, while many people will leave organized religion as the world opens up, opportunity costs grow, and Church membership becomes more of a choice rather than a habit or inertially driven behavior, those that stay will be provide for a more spiritually-rooted Church, and I believe the fruits of the gospel will become more apparent to those who have ears to hear. As President Eyring said last weekend:
The rising generation will become the nurturers of the generation to follow. The multiplier effect will produce a miracle. It will spread and grow over time, and the Lord’s kingdom on earth will be prepared and ready to greet Him with shouts of hosanna.
I believe he was speaking prophetically here, and that the best days of Church growth are ahead of us.