The Greeks have a reputation for being quite superstitious. Among their beliefs, they think that if you see a black cat and a priest on the same day, it is an omen of bad luck. Another act they try to avoid is saying a word at the same time as another person. You have all the information in: «Traditions of the world: cultural and social customs«.
You have all the information in: "Traditions of the world: cultural and social customs".