‘Speak of the Devil’ — And He Will Appear
Definition: Said when a person appears just after being mentioned. (Source: New Oxford American Dictionary)
The phrase ‘speak of the devil’ is nowadays only used in a joking and relaxed way when someone who was recently being discussed enters the room.
But before the 20th century, this idiom was not used in such a light context. The entirety of the phrase went like this:
“Speak of the Devil and he will appear.”
This phrase originated from England and was commonly said as ‘Talk of the Devil’.
This phrase appeared first in the Italian writer Giovanni Torriano’s Piazza Universale, 1666:
“The English say, Talk of the Devil,
and he’s presently at your elbow.”
In the 17th century the term was well known. This idiom shows the superstition that speaking the Devil’s name will cause harm. There are many names for the Devil that have stemmed from this belief:
Prince of Darkness, Fallen Angel, His Satanic Majesty.
Referencing the Devil was thought a very unlucky endeavor.
The usage of this phrase gradually over time became more lighthearted as we now use it in our modern day language.