Today’s idiom is “speak of the devil”, and it is used when two or more people are talking about another person who is not there, and then suddenly that person shows up. After that, one of the people who was having the conversation will often say, “Speak of the devil.” about the person who just came. Here are some examples:
I think we should get Adam to organize the party. Oh, speak of the devil! Here he is. Hello Adam, we were just talking about you.
What do you think of the new manager? Oh, speak of the devil. He just walked in.
A: Where is your wife this evening?
B: She said she’d be a little late. Speak of the devil. There she is. Let me introduce you to her.
So, as you can see, it’s quite simple to use this expression. It can be used when the person who is being talked about is close by or far away.
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