The source is the
World Christian Encyclopedia by Barrett, Kurian, Johnson (Oxford Univ Press, 2nd edition, 2001). I havenāt read it.
But myfavoritemartin is right, though I wouldnāt exactly call it a lie. ā33,000ā comes from the way David Barrett defined ādenomination.ā He restricts it by country, leading to 242 Catholic ādenominations.ā (In 238 countriesā¦?)
He did the same thing with other international churches. So we can assume, for example, that there are 238 Lutheran churches listed, too, when there should be only one.
So that number of 33,000 is obviously off by a great deal.
I have found that the numbers can be tweaked in several ways. For example, are the various ānon-denominationalā churches listed separately? If listed as a single denomination, it could change the numbers significantly. Again, there are splits in the mainline Protestant churches, like the different synods of Methodism. Did Barrett count them separately, or together?
Hereās an article, linked to another article with numbers taken from the book - though the Catholic authors donāt seem to have considered what I said above. For instance, they happily accept ā226ā denominations of JWs, when they, too, are one church with one world headquarters in Bethel, NY.
But if you have the time, you might be able to get closer to the actual numbers by getting out your calculator and going for it. I did something like that several years ago, and came up with a number of around 3000 non-Catholic Christian denominations.
bringyou.to/apologetics/a120.htm
Hope this sheds some light,
Ruthie