“Bless you”

Whenever someone sneezes, you say “bless you” or hear someone else say these words.

Why? Why are these words spoken?

Many people have become accustomed to saying "bless you" or "gesundheit" when someone sneezes. No one says anything when someone coughs, blows their nose or burps, so why do sneezes get special treatment? What do those phrases actually mean, anyway? Wishing someone well after they sneeze probably originated thousands of years ago. The Romans would say "Jupiter preserves you" or "Salve," which meant "good health to you," and the Greeks would wish each other "long life." The phrase "God bless you" is attributed to Pope Gregory the Great, who uttered it in the sixth century during a bubonic plague epidemic (sneezing is an obvious symptom of one form of the plague).

When? When did this saying originate?

It entered the English language in the early part of the 20th century, brought to the United States by German-speaking immigrants.

How? How did this saying originate?

 It's expected we'll say "Bless you!" (Or "God bless!") when someone nearby sneezes, but does anyone really know why we do this? Are we trying to protect the sneezers from evil spirits? Are we fending off the Devil? Is this a remnant of an ancient recognition that sneezers aren't long for this world, thus we commend their souls to God even as we wash our hands of them? Are we congratulating them on their impending good luck? (As silly as this may sound now, sneezing was at one long-ago time seen as a fortuitous portent.) 

Where? Where did this saying originate?

The exchangeable term "gesundheit" comes from Germany, and it literally means "health." The idea is that a sneeze typically precedes illness.