The expression is intensely engrained into Western culture. Whenever someone sneezes the instant response from a nearby person is “God bless you,” or “Bless you!” Most of us never even think about it, and the expression continues to be passed down to each generation.
Why do we say it? Where did it appear from?
The phrase itself comes directly from the Old Testament and the custom of the early Christians. In the book of Numbers we see it rendered, “The Lord bless you and keep you!” (Numbers 6:24). Other case are found in the liturgy, such as the phrase, “The Lord be with you.” It was a common phrase for Christians and used in many different circumstances.
The expression wasn’t attached to sneezing until the 7th century. the expression “originate from a papal order supposedly issued during the rule of Pope Gregory I. Also known as Gregory the Great, he assumed the popehood in 590, at a era when the bubonic plague was raging through Europe. An early sign that the virus had entered a victim was a sneeze, so on or around 6 February 600 AD, the Pope is attributed with suggesting that God’s blessing be offered to anyone who sneezes in order to defend against falling ill.”
There was another tradition that stated a person is vulnerable to the devil when they sneeze, so saying “God bless you,” prevents any malicious activity from occurring.
Regardless of the exact origins, the expression is a biblical prayer that asks for God’s blessing upon someone who is suffering from sickness. It is a kind gesture, one that, if prayed with faith, calls down God’s grace upon someone in need.