The man, named Xu, made the oath in front of a crowd of neighbours in Fuqing city, reports Southeast Express.
He vowed that he had never borrowed money from Mr Huang, who claimed Xu borrowed 500 yuan, the equivalent of £40, from him three years earlier.
"He borrowed 500 yuan three years ago from me for a friend's marriage gift, but he has denied it ever since then," said Huang, who went to Xu's home to demand payment.
"I told him that if he dared to swear to God that he didn't owe me the money, then I would waive his debt," said Huang.
Xu made the oath, but was suddenly struck by lightning a minute later.
He was immediately taken to hospital where doctors confirmed he had been hit by lightning. He is expected to make a full recovery.Found this Post interesting? Discover more Curious Reads.