May The Force Be With You / May the 4th Be With You works as an on-screen good-luck send-off, spoken whenever a Star Wars character heads into a fight they might not survive4. Fans took it beyond the films by seeding it into everyday speech and internet posts every May 4, a date picked because saying 'May the 4th' puns directly on 'May the Force'7. In 2017, Buckingham Palace confusion around a supposedly urgent royal meeting collided with the date, and Twitter users spent hours photoshopping Queen Elizabeth II onto Star Wars Day signs6.

Among film buffs, the catchphrase carries extra weight because the American Film Institute placed it on its list of the top movie quotes in 2005, ranking it inside the top ten of '100 Years... 100 Movie Quotes'3. Star Wars Day itself grew out of a joke that British newspapers were already running by 1979, well before internet fandoms could organize around a shared hashtag7. The result is a line that plays two roles at once: an in-universe blessing between characters, and an outside-the-fiction anchor for one of pop culture's biggest annual pun days.

The catchphrase typically works as a sign-off before someone attempts something risky, tedious, or otherwise dread-inducing, borrowing the exact rhythm Han Solo uses in 'A New Hope'4. On May 4, 'Force' is commonly swapped for '4th' in captions, tweets, and store promotions, and the shared date lets brands and fans reuse the joke without having to reference the original scene7. Photoshopping public figures into Jedi robes or Star Wars scenes is a common May 4 convention, as Twitter did during the 2017 Buckingham Palace speculation when users placed Queen Elizabeth II next to 'May the Fourth Be With You' signs6.