Rabbi

Rabbi (from Hebrew rav, great, with first-person suffix: my great one or my master) was an honorific title of address for a teacher of the Jewish law. In the first century it was not yet a formal ordination title (that usage developed after 70 AD) but a respectful form of address for a recognized religious authority. Jesus was addressed as Rabbi repeatedly by his disciples, the crowds, and even by Nicodemus (John 3:2), indicating that he was recognized as a teacher of comparable standing to the Pharisaic sages.

Jesus himself, however, warned his disciples against seeking the title: But you are not to be called Rabbi, for you have one teacher... and the greatest among you shall be your servant (Matthew 23:8–11). John 1:38 translates Rabbi as Teacher for his Greek audience. Rabboni (my great master) was a more emphatic form used by Mary Magdalene at the resurrection (John 20:16) and by the blind Bartimaeus (Mark 10:51).