Why Is Friday The 13th Unlucky?

Can you honestly say that you’ve never felt a slight pang of concern when waking up on the morning of Friday the 13th?

You’re not alone. Maybe it’s triskaidekaphobia, the fear of the number 13, that gets you down. But, if 13s don’t bother you unless it’s Friday, you might be susceptible to what’s sometimes known as paraskevidekatriaphobia or friggatriskaidekaphobia, instead. Whether you plan on purposely walking under ladders with black cats this Friday or staying tucked in bed, it’s worth diving into why Friday the 13th has a bit of a reputation.

Read about the history of Friday and learn some more trivia here.

Why do people fear the number 13?

First, let’s get into 13. While many cultures have an issue with the odd number, there’s no one set of circumstances that would make it decidedly unlucky. Common theories behind the fear of 13 include

  1. Viking lore, where the unsavory Loki is believed to be the 13th god in the Norse pantheon
  2. a biblical reference to the 13 people reportedly sitting at the table for Jesus’s last supper
  3. numerology, where 13 is in low regard because it follows 12, a very “complete” number. But, if you ask an architect why they omitted the 13th floor from a high-rise, they probably won’t bother citing a source for their superstition.

Where does the word Friday come from?

Friday was named for one of two Norse goddesses, Freya or Frigga, and there exists to this day a great deal of debate about the origin of the day’s name. Friday is just one of the days of the week named after a mythological figure. Tuesday derives its name from Tiu, war god of Anglo-Saxon mythology. Wednesday gets its name from Woden, the Anglo-Saxon equivalent of Odin. Thursday is named for Thor, hammer-wielding god of thunder (and son of Odin). While exclaiming “TGIF” is common now, some traditions consider “Frigga’s Day” to be unlucky.

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Why is Friday the 13th unlucky?

The day’s connection to a Norse goddess is not the only theory as to why Friday the 13th is unlucky though. Some Christians believe that Christ was crucified on a Friday. Friday was also once known as “hangman’s day” in ancient Rome and Britain because it was usually the day that condemned people would be hanged.

It’s likely that these two sets of unlucky lists just add up to make Friday and 13 an intense combination for superstition. And of course, if you’re expecting unlucky things to happen, you might even change your habits on days like this. Multiple studies speculate that businesses lose millions of dollars in revenue each Friday the 13th because some people avoid regular behaviors like traveling or making investments.

The term and superstition related to Friday the 13th rose to great prominence in 1980 with the release of the slasher horror film Friday the 13th, starring the undead, machete-wielding, hockey goalie mask-wearing murderer Jason Voorhees (first played by Ari Lehman).

WATCH: Four Reasons Why Friday The 13th Is Unlucky

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