(WTAJ) — “Bless you” or “God bless you” is a phrase most Americans say when someone sneezes, but why do we say it and where did it come from?

The exact origins of the saying are unclear. However, there are a few theories and possibilities about where it may have come from.

According to Dictionary.com, two common theories involve demons and spirits, hence the need to bless someone. It was believed that a person’s soul would momentarily leave their body which would leave it vulnerable to being captured by the devil. It was also believed a person who sneezed expelled evil spirits from their body and the blessing was used to prevent the spirits from reentering.

The Massachusetts Institute of Technology (MIT) International Students Office found the phrase may have originated in 14th-century Europe during the bubonic plague. People who fell ill with the deadly disease would be offered a benediction through the phrase “God Bless You.”

Regardless of its origins, saying “Bless You” is now normally used as a way to show politeness and manners. Some people even use the phrase “Gesundheit” which is a German word that means ‘health.’

No matter which phrase you say, the gesture is traditionally meant to wish someone good health and to fight off any illnesses that may have caused them to sneeze.