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Monday, December 5, 2016

Is the World's Muslim Population Growing Faster than the Christian Population?

We could perhaps call it the Religion Race. The two great proselytizing religions in the world are Christianity and Islam. Christianity had a seven century head start on Islam, but Islam has been steadily catching up with Christianity in terms of the overall number of adherents. Thanks to Abu Daoud for pointing me to a recent assessment of where we stand globally.
Bottom line: both Christianity and Islam are growing faster than the world population (so the world is becoming more religious); and Islam is growing faster than Christianity, so the % Muslim in the world is increasing.
These numbers are based on projections made by the Center for the Study of Global Christianity at the Gordon-Conwell Theological Seminary in Massachusetts. Although they use UN Population Division projections for their baseline numbers, they clearly have to make their own estimates of the population by religion. Their data project that by 2050 there will be 3.4 billion Christians, accounting for 35% of the world's projected population of 9.6 billion. By comparison, they project a total of 2.7 Muslims in 2050, representing 28% of the world's total. 

Meanwhile, last year Pew Research published its projections of the world population by religious affiliation. They projected a total of 9.3 billion people in the world by 2050, of whom 2.9 billion are projected to be Christian (31%), and 2.8 billion Muslims (30%). So, we see that the Christian group making projections has a higher number for members of its religious group than does the secular research organization. Does that surprise us? I think not. In either case, the conclusion stands that largely through birthrate differences, the Muslim population of the world is growing faster than the Christian population.


  1. Thanks for commenting on this article. But let me ask you opinion on another article relating to Islam and Christianity. This is a census on converts from Islam to Christianity:

    1. Very interesting study, but keep three things in mind: (1) the numbers are still fairly small in comparison with the overall totals; (2) there are also conversions the other direction; and (3) the Pew Report does include their estimates of conversions. A final note: What's going on with conversions in Indonesia? I had not heard about that.

  2. Good questions. 1) Yes, the answers overall are very small in relation to global numbers. But in relation to historical numbers of converts the increase is exponential. 2) There are conversions the other direction, but some estimates in the USA state that some 80% of those are not enduring. 3) The Pew report does not address conversions, but the Miller-Johnson census does. It is, to my knowledge, the only research that attempts to do so.

    Final Note: The full story is told in Avery Willis Jr, Indonesian Revival (1977). The beginning of the upsurge in conversions had little to do with missionaries or ministry, but a lot to do with the contest between atheist communists and fundamentalist Muslims, both of who were pathetic to the venerable if very syncretistic and folkloric Islam of many people. When forced to choose between fundamentalist Islam and atheistic communism a large number of folk Muslims opted for an indigenized and flexible form of local Christianity.

    1. For the record, the Pew report does indeed address conversions--see pp. 180-183 of the full report. And, thanks for the info about Indonesia--very interesting!