This could be a lesson for married men: Never forget the year of marriage.
Chinese singer Jason Zhang panicked when he made this faux pas at his concert in Qingdao on Saturday (June 1).
He was chatting with his guest, comedian Xiaoshenyang, when he recalled the day he married his wife, television host Xie. He said on stage that it was in 2010, before he realised in horror he had made an "unforgivable" mistake.
Zhang, 36, married Xie Na, 38, in September 2011. They have two daughters.
Perhaps to atone for his mistake, Zhang wrote on Weibo on Sunday: "I have decided not to say anything. I must kneel on the washboard to ease my pain. I can wash the clothes at the same time too."
Kneeling on washboard is considered in the past to be a punishment for a husband who has made mistakes.
Xie seemed to have come to her husband's rescue when she re-posted his post an hour later and wrote: "It is true I wanted to marry you in 2010, but it is annoying that you married me only in 2011."
However, she concluded her post by saying: "Washboard? Let's try it on a remote control without changing the TV channel."
Zhang rose to prominence after winning the reality singing competition My Show in 2004. He released his debut album, The First Album, in 2005.