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Less about what we do less of, more about what we do differently

Some evangelistic methods leave you feeling like Christianity is all about dealing with the past.

We need forgiveness because we have sinned. And, we need Christ in our heart so we won’t keep on sinning.

This is very true. But Christianity – following Christ – doesn’t stop there.

If we make it mostly about dealing with our sins, we run into the problem of people who have lived (at least in their view) “basically good lives.”

Our response to that is, of course, “all have sinned” – so even the “tiniest sin” can separate us from God.

And that leads us into lots of arguments that are basically works-based thinking.

Perhaps we ought not focus quite so much on what we are being saved out of, and think more about what we are being saved in to.

Perhaps it’s less about the past we leave behind and more about the future we walk toward.

Perhaps it’s less about having sins forgiven and more about becoming a citizen of the Kingdom and a subject of the King.

Perhaps it’s less about what we stop doing, and more about what we start doing.

The world should change because of us – not in that it does less, but that it does differently.

I am thinking of these Hero Rats this morning, and thinking – this is the sort of thing that should flow out of the Kingdom, seeking to set things right.

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The Rule of 72

The Rule of 72 is a quick if coarse way of measuring the time it takes a population to double.

First, you’ll need to figure out the growth rate of your population. This is pretty simple: if you’re calculating for a year, then it’s the newer population divided by the older population (e.g. pop2010/pop2009). If you’re calculating for a longer period of time (say a decade), then it’s: (new/old)^(1/time_period). So, for example, for a decade, it would be (new/old)^(1/10). (The ^ symbol is “to the power of”; any decent spreadsheet will do it.)

The Rule of 72 is: divide 72 by the population growth rate to get the number of years to double. If the growth rate is 4%, 72/4=18, so 18 years for the group to double in size.

If the doubling rate of the group is significantly faster than the doubling rate of the population, you’ll have a chance to double or quadruple in size in the same time the population does so once. For example, if the time-to-double is one-quarter that of the national population, it’s possible 4 “doubling generations” could be done in the same time the national population adds one. If the national population growth is 2%, you’d need growth of about 8 to 10% on a regular basis to reach those kinds of levels (72/2 = 36 years to double, 72/8 = 9 years to double.)

That sounds difficult, but 10% growth just means each small group of 10 adds one new member per year. That’s really not that remarkable a growth rate. Let’s say you start with a church of 100. At an 8% growth rate, by the end of a decade you would have a church of 200 (72/8=9 years). Keep that sustained, and by the end of 16 years you would have a church of 400 (in generation 2, the 200 doubled to 400). Do another decade and you will reach 800. Another decade to 1,600. So, at an 8% growth rate, in 40 years you have 1,600 people.

Now, let’s reverse-engineer. Let’s say you have 100,000 people, and you want to have them all be in a church in 40 years. What kind of growth rate would you need? It’s a fairly simple equation to run in a spreadsheet: you’d need a sustained 20% growth rate with very few dips over a 40 year period. How can you do that? Have everyone in a church in a small group, and each small group of 10 adds 2 new members every year, without fail. In 40 years, the church will have grown to 100,000 people.

Sounds easy, but in practice it’s not. The larger the organism gets, the harder it is for it to grow. This is why it’s very important, early on, to train, coach, and encourage all of your people to be making disciples and multiplying.

On speed of growth as a corollary to health of church

Who creates the future

The future may indeed be experienced by the resilient
– those that can endure the present to see what happens, happen
– the non-risk-takers
– the preservers
– the avoiders of danger

But they will not be the ones who create the future.

Future creators leave the now for the future before the future gets here.


No matter where you are in the world, no matter who you are working among, no matter how many believers you have, it will typically not take more than 17 “doublings” of the Christian population to saturate most districts.

20 to 25 doubles would suffice for nearly any province. 32 doubles would see the entire world Christian–even if you are starting with just one person.

Early doublings can be easy. Later doublings are hard.

The biggest question in terms of when the world will be reached is–how long does it take for a given group to double in size?

If it takes a year to double, then you’re looking at, minimum, about 20 years to saturate an area (provided you maintain speed). If it takes 20 years to double, then you’re looking at 400 years.

The longer it takes to double, the more can happen “in the meantime” to prevent the doubling from ever taking place. Speed of doubling is your ally. Anything that slows you down increases the risk it will never happen.


Are Muslims the fastest growing religion, and why?

Dear Justin,
This is the latest big news here…and around the world:
My question:  what do you think of this?
And, is it true that much of this growth is from “switching” or is it almost all biological growth?  What I had understood in the past was the Islam is in fact the fastest growing religion around the world—and continues to be—but not in terms of conversion growth. In terms of that, evangelical Xnity is #1.
What say ye?

It depends on whose data you are looking at. I usually use figures out of the Center for the Study of Global Christianity (publishers of the World Christian Encyclopedia, World Christian Trends, Atlas of Global Christianity, and World Christian Database). CSGC also is a co contributor to the World Religions Database which informs in part Pew Research.

Pew & CSGC differ slightly over projections. CSGC has published its differences here. In brief, although the analysis of the two (and the methodologies) are very similar, CSGC projects 3.4 billion Christians (vs Pew’s 2.9)–about 500 million more Christians.

Part of this is because CSGC looks more deeply at non-traditional forms of Christianity, such as house churches, which are mostly “under the radar.” One example is that while CSGC’s estimate of China’s current Christianity is in excess of 100 million, Pew’s is about 60 million.

The bottom line? CSGC estimates that Islam is now the fastest growing major religion (1.88% per annum), although it is not the largest religion. By 2050, the two disagree on which will be the major religion. I think projecting that far out is a bit of an academic exercise: it could be impacted by any number of factors.

As for the source of growth of Christianity: yes, it is largely demographic. Most Muslim dominated countries have birth rates much higher than the global average. For examples of this, look at the largest Muslim countries. Or, this chart, from Pew:

religionists fertility rate


Based on CSGC data, “conversions” factor in to Islamic growth largely in a couple of places (among some subsets of US populations, and in northern Nigeria), and through the force of marriage (in many places if a Christian woman marries a Muslim man she becomes Muslim–at least from a “legal” perspective if not from a “heart” perspective). By far, however, the largest portion of Muslim growth is from births to Muslim homes.

What I think we must do to count the task finished

I’ve been doing a considerable amount of thinking about “the task” of missions and “when the task is finished.” Some of my thinking has been very passionate, and not very structured. In this, I’m going to try and be a little bit more structured.

Two comments on “Jesus wants the whole pie” are instructive in this.

First, John Lambert commented “closure is just the beginning” and “yet we have still not made initial breakthroughs in a large number of unreached peoples.” This is very true, and it is the driving force behind the work of Finishing the Task and its related groups. Every group needs to at least be begun in order to be finished. Or, to put it another way: if we don’t begin, the task isn’t presently “finishable.” And there are still lots of peoples where this is the case.

Second, Jim comments: “one of the unintended consequences has been the marginalization of Christianity in majority non-Christian populations.” He goes on to use the Thai as a classic example (see the original post for a full read). Now, here’s a people group – the Thai – that are clearly engaged: there are missionaries among them (although, as Jim notes, there are proportionally far fewer missionaries amongst the majority Thai than amongst the tribals). There’s even an indigenous church among them (although quite small compared to other groups). So, are the Thai “reached”? “Finished”?

The classic definition of “reached” is a group having a church that can evangelize the group to its “borders” without cross-cultural assistance. The classic definition of ‘reached’ is really about whether the role of the cross-cultural missionary is finished. Can I count myself done?

Let’s use the Thai church as an example. Is the task of mission done? Are the Thai “reached”? Can the Thai church finish the task without cross-cultural assistance? This is a hard and complex thing to measure. Let’s start with a simpler question: Is the Thai church doing this? Jim argues no, and the data seems to me to agree.

Given its current methods and history, organized Christianity in Thailand is growing at 2.99% p.a., according to the 2010 Atlas of Global Christianity. In fact, take this further: over the past century, Christianity has averaged a growth rate of 1.4%. The recent growth rate is faster than the population AGR of 2.16%–but only barely. Just because one population is growing faster than another doesn’t mean it will catch up any time soon. (This is also an important principle to keep in mind when you’re thinking about scary stories of the “Islamization” of _x_, where _x_ can be any place in the world.) Let’s look at this growth rate charted for Thailand:

thai church growth 2010-50

The size of the church is very small: just 850,000. Remember “percent” means “per hundred.” Every year, the global population is adding 216 people “per hundred” – but there are many more “hundreds” in 65 million people (the total population) than there are in 850,000. If the current growth rate is maintained, the two bars won’t cross any time soon.

So, are the Thai “reached”? Is the task finished? If you define the task as planting a church that can reach the whole of the group, then the answer is yes: given the right strategy and enough time, this church could reach 65 million. If the task is a church that “will” reach the whole of the group, a church with the vision, resources, scalable strategy, etc., within a specific time frame (say one or two generations), this chart clearly says–no, the task is not finishable.

Now, it is true that what appears to be unfinishable now might actually be finishable later if you are using an exponential growth strategy. Look at this chart as an example:


The bottom left section (“Looks like it won’t be finished”) looks remarkably similar in some ways to the Christian portion of Thailand in the chart above. And exponential growth looks like this: it goes and goes and goes and then suddenly achieves “lift off.” It begins to “scale up.” And then the task is rapidly finished.

But this idea relies upon the kind of church growth strategy being used. To ascertain whether the task is finishable using this approach, we must assess whether the current strategy has the capacity of exponential growth, and how far it can scale. Can it reasonably scale to 100% of the population? What are the barriers along the way? If it can’t scale, the task is not finishable.

We can measure this by asking what kind of growth rate would be required to “finish the task” (reach everybody) within a give time frame, and asking whether the strategy can achieve that level of growth. How to answer this for Thailand?

Here’s growth at 8% per year. At nearly 50 years an upswing is being seen, but the two lines aren’t close to intersecting–and this is with a church growth rate four times that of the population!



Here’s 12% per year. This would do it by 2050–a growth rate 6x that of the overall population (and keep in mind these sorts of rates would also be needed for a small Muslim population, for example, to overtake a larger one).


I’m not saying this is easy. All I’m saying is this: in many places, the good that now being done will not get Christianity to the end goal. It will only preserve the status quo in which the church remains stagnant at 33% of the global population (as it has for the last 100 years).

I think before we count a group as “reached” or the task “finished,” we have to ask this question (which I posed another way in Jesus wants the whole pie): will the task be finished all the way?

The Whole Church may have very well finished the “engagement” part of the task. The Church may even have finished the “plant a church” part of the task. But if the way these tasks have been finished prevents the future tasks from being finished all the way–are we really finished? Have we done our part?

If a church has been planted, but planted in such a way that it does not have the capacity, will, resources, strategies, whatever, to actually reach the population (and this is evidenced in the results it is presently achieving and markers that it will scale up), then… is the population segment (of whatever form) reached?

It may seem like I’m picking on the Thai. This is just one example. You could pick lots of other places and find exactly the same problem. This is why movements, and engaging lots of places, is so important to me.

When people group thinking can fail: Jesus wants the whole pie

“Long ago, far, far away,” the church used to think of the Great Commission (‘go into all the world, make disciples of all the nations’) in terms of countries or nation-states.

After Winter’s 1974 address to the Lausanne Congress on World Evangelization, that began to change. The mission enterprise began to focus more on peoples, and specifically on unreached peoples.

A people specific focus is harder. The boundaries of countries are (mostly) clear. People group boundaries are not always so.

  • Language is fairly obvious: to reach the Turks, you will (mostly) have to learn Turkish. While this is usually the ‘hardest’ boundary, the influence of second languages, and growing/dying languages, can soften and blur it.
  • Location still plays a role: reaching the Turks in Turkey represents one set of problems, whereas reaching Turks in Germany is a different set. The massive increase in diasporic movements have challenged our ideas of peoples. Are 100 Saudis in America a people group? How big does a group have to be, to be a people group? When do they cease to be Saudis and get assimilated into a bigger group?
  • Caste and sociopolitical divisions occur less frequently, but where they exist they are strategically significant. This is the biggest difference between how Joshua Project handles people groups, for example, and how others (like the World Christian Database) do. Whether we should pay attention to caste at all is a genteel argument in some circles.
  • Another specific kind of location is increasingly important – the ‘melting pot’ nature of cities. Sometimes boundaries between peoples in cities remain clear (‘Chinatown’ is the stereotype that springs to mind); in other places they begin to blur as people assimilate. Trying to reach individual peoples within a city may be less possible than simply reaching the city as a whole.

These boundaries affect not just the spread between peoples (e.g. between Japanese and Koreans). When a group is large enough, you can’t reasonably speak of reaching ‘all’ of the group with one strategy. There are boundaries inside the people group, between individuals.

Reaching Istanbul does not automatically reach Ankara; reaching urban cities does not automatically reach rural villagers; reaching college women does not automatically mean reaching housewives, who in some cultures are very secluded.

This is the important value Winter was getting at in ’74: segments within a society are cut off from the Gospel because the choices we, who have the Gospel, are making about which languages we use, what methods we use, who we work with, where we work.

Just because we are now focused on peoples, not countries, doesn’t mean we are actually ‘winning.’ We can fall for the same problem within peoples that we fell for within countries. We can reach everyone in Istanbul… in a way that does NOT multiply out to the rest of Turkey. We can reach everyone in Beijing in a way that does not extend the Gospel to Xinjiang. We can reach everyone in Jakarta in a way that does not get to the other islands of Indonesia. And this is the exact same failure.

Our choices can limit who hears the Gospel, and thus “in a sense” our choices–or lack thereof–determines the eternal destinations of some.

(There’s a ton theologically in there, and you might not agree with it–on some days, I don’t agree with it–but nevertheless, whatever we think, we need to be very mindful of the eternal implications of our strategies.)

The task Jesus gave us isn’t as simplistic as ‘plant an outpost community within each large group’ be it a country, city-state or ethnic group. This reduces ‘make disciples of the nations’ to its minimum: ‘I am satisfied if you make a few (perhaps 12?) disciples of the group, no matter how large’ equals “make disciples of every nation” (he didn’t say how many disciples…).

I believe Jesus’ heart for the world (read John 3) demands we be thinking about how to aim for the maximum, not the minimum, completion of the task. We need to think about how to disciple the whole world. We need to think about how to invade every last, tiny segment with the Good News: not just the pie, but every ingredient of the pie.


What we can learn about churches from yards

Last Saturday, I spent a lot of the day (along with my wife & kids) working on our yard. One of the big tasks we undertook contained some lessons.

We started with this:


In my wife’s words, we aren’t really huge yard people. Eventually this piece would get overgrown with weeds during the year. So, we decided it was time to take it out and return the land to grass. This was a huge task.

In particular, the big bushy plant had to be pulled out at the roots, which meant digging down deep with a shovel.


The plant was pretty resistant. We had to tear it out piece by piece. Anything comes out given enough time, work, tools, pressure and destructive force.

Finally, we had the plant out, ready to throw on the garbage heap:


Afterward, we spent several hours hoeing, tilling and digging up all the weeds in the dirt (and discovering about a dozen grass snakes). At length, after a day of backbreaking work, we had this to show for our efforts:


Throw some grass seed on it, and in a few months you won’t be able to tell a plant was ever there.

Now–think about this in terms of the Parable of the Sower, and consider the church as a rooted plant in one spot. Beautiful, when it’s there: but this particular little bush wasn’t multiplying at all, it wasn’t competing with the weeds, and it had no defenses against our shovel.

The weeds, on the other hand, sprout practically overnight, and no matter how many times we dig them up–more come. They rapidly multiply and resist all efforts to eliminate them.

Is there a parable in this?


Would closing the defection gap lead to more missionaries for the unreached?

One of the diagrams that you drew at the Perspectives class the other day showed the inputs and outputs of people into the kingdom as well as into unbelieving homes. It was a circle that had 3 layers: the unreached, evangelized, and believers if I am not mistaken. One of the numbers that I guess didn’t surprise me, but made me wonder “how can we do better in THAT area” was the output from believers that lose their faith or if one could say “deconvert”. Is this an output that will ever be eliminated? Is that even possible? If this output decreases significantly, would that give the church/believers enough momentum to really tackle the remaining task? Most of these seem hypothetical I guess, but still learning about that output made me sad.

Each year, globally, on average, we have 45 million new babies born to Christian homes. Thanks to Christian mission and evangelism, about 15 million people convert from non-Christian faiths to Christianity. But at the same time, each year, 12 million people defect from Christianity–some to other religions, some to no religion at all. When I cover this in Lesson 9 of Perspectives, it’s always shocking to people, and I often feel a lump of sadness myself.

Defection is, in my opinion, mostly–though not entirely–a function of discipleship. I don’t think it could be entirely eliminated, but I think it could be strongly reduced if we had better discipleship processes for believers.

At the same time, discipleship processes that were strong enough to reduce defection rates ought also to be strong enough to instill a greater passion for the heart of God and obedience to His Word, and this would correlate to rising numbers of mission workers to the unreached. Short answer: yes, I think it would.

Justin Long
If you have a question about missions, email me and I’ll answer it here.