The theory was summarised like this, The number 5, Camping concluded, equals "atonement." Ten is "completeness." Seventeen means "heaven." Camping patiently explained how he reached his conclusion for May 21, 2011.
"Christ hung on the cross April 1, 33 A.D.," he began. "Now go to April 1 of 2011 A.D., and that's 1,978 years."
Camping then multiplied 1,978 by 365.2422 days - the number of days in each solar year, not to be confused with a calendar year.
Next, Camping noted that April 1 to May 21 encompasses 51 days. Add 51 to the sum of previous multiplication total, and it equals 722,500.
Camping realized that (5 x 10 x 17) x (5 x 10 x 17) = 722,500.
Or put into words: (Atonement x Completeness x Heaven), squared.
"Five times 10 times 17 is telling you a story," Camping said. "It's the story from the time Christ made payment for your sins until you're completely saved.
"I tell ya, I just about fell off my chair when I realized that," Camping said.
Yes, people believed this.
Not only that, but this was Camping's second attempt. He'd originally specified the date as September 6th 1994, another date that passed uneventfully.
Based on the position of the stars at 6pm local time, one might attempt to identify exactly where in the heavens this rapturous god lives.
And spread they did. Peoples from around the world, including China and in Vietnam, where thousands of ethnic Hmong, having heard Camping's radio broadcasts converged on Vietnam's north western Dien Bien province for the event.
Of course the majority of the nut-jobs who believed this story were in USA. As well as those who gave up all their possessions ready for the rapture (one must ask, upon what criteria were they so sure they'd be members of the 200 million?) others even stopped their children's college funds as, of course, they wouldn't be needed.
One would not be surprised to hear that the sceptics were in on the deal as well, offering to buy all the (unneeded) worldly possessions of those about to ascend for a rather low price - what would the raptured need the money for, anyway?
Since Camping made it very clear that the rapture would take place at 6pm (but, did he mean 6pm standard time or daylight savings time?) in each time zone, it might be safe to assume that the direct path to god's salvation would directly overhead at that time.
Clearly, the message was directed primarily at his North American audience, so let's assume Daylight Savings time.
Looking at any astronomical simulation package, I've used Stellarium, it is clear that the most prominent astronomically equatorial feature (it has to be on the astronomical equator in order to be visible from all parts of the Earth) is the constellation of Cancer (the Crab).
So, with as much precision as Camping used to set the date, I here and now assert that god lives in the zodiacal sign of Cancer.
And thus, the world's bemused were watching for any sign that the rapture was actually taking place.
Nothing happened. In fact more than that, no-one in New Zealand seemed to be paying it any attention whatsoever and there were no visible reports in any online news sites to suggest they could even report a negative result.
Roll on to Australia where Twitter lit up a little after 6pm with everyone saying things to the effect of "I saw nothing, did anyone else see anything?"
Right now, the Rapture has passed by three of the four continental US time zones with no reported activity and will strike California a little after this item is published (and updated if anything actually happens).
Judging by the total failure of Camping's second prediction, we can only assert that he has just one more chance to get it right - "third time lucky," as they say.