Jesus turned, and saw them following, and said to them, "What are you looking for?" They said to him, "Rabbi" (which is to say, being interpreted, Teacher), "where are you staying?"

 In the ancient world nearly everyone had two names. Greek was the universal language and nearly everyone had a name in his own native tongue, by which he was known to his friends. Thomas was the Aramaic and Didymus (Didumos - G1324) the Greek for a twin; Tabitha ( G5000; compare H6646) was the Aramaic and Dorcas (Dorkas - G1393) the Greek for a gazelle. Sometimes the Greek name was chosen because it sounded like the Aramaic name. A Jew who was called Eliakim or Abel in his own tongue might become Alcimus or Apelles to his Greek circle of acquaintances. So then Peter ( G4074) and Cephas ( G2786) are not different names; they are the same name in different languages. 