Speak of the devil Informal

Said, often half-jokingly, when a person shows up or calls right after being mentioned in conversation.

It’s a light, reflexive exclamation rather than a genuine accusation, usually met with a laugh from everyone present, including the person who just arrived.

The phrase is a shortened form of the older warning “speak of the devil and he shall appear,” reflecting a genuine old superstition that naming an evil spirit aloud could summon it — a belief once taken seriously enough to make people avoid saying certain names directly. What’s striking is how widespread the underlying joke-superstition is across unrelated cultures, each substituting their own locally feared or symbolically dangerous figure: French says “quand on parle du loup, on en voit la queue” (“speak of the wolf and you see its tail”), Spanish uses “hablando del rey de Roma, por la puerta asoma” (“speaking of the king of Rome, and through the door he comes”), and the fifteenth-century Chinese novel “Romance of the Three Kingdoms” contains a strikingly similar construction about the warlord Cao Cao appearing the instant his name is spoken. This pattern, appearing independently across cultures with wolves, kings, warlords, or devils standing in for one another, suggests a shared human instinct for this specific superstitious joke rather than one culture borrowing it from another.

We were just talking about Sarah, and speak of the devil, she just walked in.

I was about to call him — speak of the devil, he’s calling me right now.

Speak of the devil! We were just discussing your project.

A: I wonder how Tom’s doing. B: Speak of the devil, there he is.