According to some, the title "rabbi" or "rabban" was first used after 70 CE to refer to Yochanan ben Zakkai and his students, and references in rabbinic texts and the New Testament to rabbis earlier in the 1st century are anachronisms or retroactive honorifics. Other scholars believe that the term "rabbi" was a well-known informal title by the beginning of the first century CE, and thus that the Jewish and Christian references to rabbis reflect the titles in fact used in this period.