Pope Francis might be washing his mouth out with soap today.

The People's Pope used some rather unholy language at the Vatican on Sunday when he mistakenly dropped a crude Italian slang word during his morning sermon.

The slip came while he was addressing hundreds of people from his window overlooking St. Peter's Square. Instead of saying "caso" meaning "example," Pope Francis said "cazzo," a vulgar Italian word for a male body part.

The pope maintained his composure, but people watching did a double-take, wondering if they really heard what they thought they did. The moment has since gone viral online.

From taking selfies to admitting he once worked as a bouncer at a nightclub, Pope Francis has surprised the world with his unprecedented ways. No one, however, expected profanity to be one of them.