"Bless You"

People say bless you when you sneeze due to a custom that derived directly from the time of the bubonic plague in AD 590.

Whenever someone was witnessed to be sneezing, it was viewed as a warning symptom of the plague, and so many would answer "God bless you!" in response.

This saying was often said in hopes of counteracting the disease (i.e. someone says, "God bless you," God will bless you and uplift the virus).

This saying originated in Europe during the time of the plague, from Pope Gregory who'd been raised to the term of papacy in that time, and wanted to prevent spread of the disease through extensive prayer and worship.

Even today, we all continue to say this, although the "god" has likely been dropped due to the political world that we've evolved into today. It has become a custom nearly everywhere, and is often considered polite to say so when someone sneezes. I honestly find it hard to believe that a tradition could've descended so far, and extended into so many regions. I'm so used to saying, "bless you," that I didn't even realize it was a tradition because it was inbred to me as a child. Cool, right?