I think it comes from a longer expression: " Speak of the devil, and he appears." Or " When you speak of the devil, he will appear." Or " When you talk about the devil, he will appear." That is a very old expression.

我认为它来自一个更长的表达：“谈论魔鬼，他就会出现。 ” 或者“当你谈到魔鬼时， 他就会出现。” 或者“当你谈论魔鬼时， 他就会出现。 ”这是一个非常古老的表达方式。