Κηφᾶς [1 verse](Aramaic word) "Cephas" means "rock" or "stone" in Aramaic. - Cephas, - This is the Aramaic word for "rock" or "stone." Note how it is translated by the Bible writer. If all of Jesus's words were Aramaic, there is no reason to pick out this one for not translating. The Gospel writer is indicated that Jesus said everything else in Greek, but used this Aramaic word. See this article.