[quote author="Don Lindsay’s FAQ on the subject"]L. Ron Hubbard is widely rumored to have said “The way to make a million dollars is to start a religion.” There are also variant rumors. For some reason, this is often mentioned on Usenet. Evidence is discussed below, but the short answer is that it’s almost certainly true.
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To summarize: we have nine witnesses: Neison Himmel, Sam Merwin, Sam Moskowitz, Theodore Sturgeon, Lloyd Arthur Eshbach, Harlan Ellison, and the three unnamed witnesses of Robert Vaughn Young. There is some confusion and doubt about one of them (Sam Moskowitz). Two are reported via Russel Miller: one is reported via Mike Jittlov: one reported in his autobiography; one reported in an affidavit; and one reported to me in person. The reports describe different events, meaning that Hubbard said it perhaps six times, in six different venues - definitely not just once. And the Church’s official disclaimer is now reportedly a flat lie.
Conclusion: He definitely said it more than once.
http://www.don-lindsay-archive.org/scientology/start.a.religion.html