L asked:
How can we know that the numbers were are hearing of people coming to Christ overseas as a result of DMM are solid? Wouldn’t they want to inflate the numbers in order to keep Americans sending more money overseas?
Are the people making decisions to follow Christ remaining in the faith 3-5 years out? Are the numbers high because we are recounting many of the same people who joined House Church A, then stop going and later join House Church B, etc. (I realize that this happens in the U.S. already with the traditional church model).
Let me point anyone asking this question first toward a more extensive essay that i wrote, “How Movements Count,” which I first published back in 2019. You can read that here.
The short version of that answer, for this page, is this.
First, we should remember that “numbers are never exact”–whether one is counting Southern Baptists in the USA, Catholics in the UK, Chinese house church members in China, or members of a movement in country x. The numbers are always changing (births, conversions, defections, deaths), for one thing. For another, a variety of difficulties in counting mean one never knows the number–and can’t–down to the last digit.
So, I would say that the numbers of people in movements are just as solid as the numbers of people in any other religious category. For example, consider: Southern Baptist Convention membership in the USA is 12.3 million (2025)–but only 4.5 million are in a worship service in a given week (Link). The difference can include non-weekly-attenders, but also long-inactive members who are still on the church membership records.
Movements tend to measure in different ways: once a movement is above a certain size, it’s not counting by individual churches (and actually, very few religious denominations in the world–even very few US denominations, do). There are a variety of ways to do it, but it’s nearly always by lines of relationship. (This is similar in some ways to how large denominations have state conventions individually report and then roll it into a national total.)
This is why the question of “church hopping between House Church A and B” can figure in to Western denominations, introducing “ghost membership” in the rolls, but doesn’t so much in movements: because movements are counting by lines of discipling relationships, not individual churches. Individual house churches can and do “bubble-and-pop” (my technical term), but lines of relationship are far more stable.
The question of “inflating counts to keep money rolling in” is a different issue, which would deserve a longer article. Here let me note that most movements raise very little money abroad. Getting money transferred is very problematic (due to increasingly tight rules about money transfer, funding entities abroad, money laundering rules, and so on), and very little is actually raised to begin with. Movements can raise some money, it’s true, for things like Bible translation or media projects–but even large movements of more than a million members are rarely raising six-figure budgets. Movements generally run on the back of lay workers, bi-vocational workers, and local business projects.