I might point out at this stage that one of the reasons we know that it was Luke who wrote the speeches of his main characters is that the speeches all sound very much alike: the lower-class, uneducated, illiterate, Aramaic-speaking peasant Peter gives a speech that sounds almost exactly like a speech by the culturally refined, highly educated, literate, Greek-speaking Paul. Why do two such different people sound so much alike? Because neither one of them is actually speaking: Luke is. To make up his speeches, he used some older materials, with preliterary traditions embedded in the speeches.