Most of the folks claiming May 21 as Judgement Day are listening to Harold Camping (
www.wecanknow.com). Citing prodigious mathematical evidence from and the self-evident veracity of the Bible, he has proclaimed May 21 as the Rapture; the day when the chosen true believers (~200 million) ascend bodily into heaven with Christ. Five months later on October 21, God will destroy the Earth and all those not raptured in Armageddon.
Sadly far too many people are doing the same as the fellow in the OP's linked article, emptying bank accounts of life savings and leaving their families to witness these beliefs to others.
Mr. Camping previously claimed September 6, 1994 was the date of the Rapture. Clearly this time he got it right.
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