Nothing to Sneeze At
An interesting historical tidbit is that the phrase "God Bless You" is
actually associated with Halloween. The Welsh believed that every time
you sneezed, you blew part of your soul out of your body. Hence, they
would say "God Bless You" to anyone who sneezed to bless their soul.
Because of this, sneezing on Halloween was to be avoided entirely. It
was believed to be extremely dangerous because wandering spirits or the
devil could capture your soul as you sneezed!