Nicodemus and the ben Gurion family
In two places, John's Gospel introduces a somewhat mysterious figure called Nicodemus. In John chapter 3 verses 1-21, Nicodemus visits Jesus after dark one evening. He is described as a Jewish religious leader, and a pharisee.
Then in John chapter 19 verses 38-42, Nicodemus helps Joseph of Arimathea to bury Jesus. We are told that he brings a large quantity of embalming ointment, which gives the impression that he is rich
There is no definite evidence of Nicodemus's existence outside the Bible. However, there are two people called Nicodemus, one in Josephus's Antiquities (14:37), and one in the Babylonian Talmud. Both were members of the ben Gurion family, 'in which...' as Blomberg says, '... only a handful of 'first' names reappear over the generations.' (The implication is that Nicodemus is one such name.)
Josephus's Nicodemus was alive in 64 BC, so he certainly cannot be the person John writes about. The Nicodemus of the Babylonian Talmud was a rich man who lived in Jerusalem during the war with Rome, i.e. the late 60s AD. The Nicodemus of John's Gospel could have been the uncle of this Naqdimon ben Gurion of later Jewish history.
The picture of Nicodemus in John's Gospel fits what we know of the ben Gurion family: they were rich, they were pharisees, they were teachers of the law and members of the ruling class. This is not proof - but it does mean that the account in John's Gospel fits the historical circumstances very closely.
Jewish tradition also speaks of one of Jesus's disciples called Nakkai, or Buni, which Blomberg identifies as a Hebrew equivalent of Nicodemus. John A T Robinson concludes that this tradition reflects reliable, independent testimony for the Nicodemus described in John's Gospel.
The source for the information on this page is 'The Historical Reliability of John's Gospel', by Craig Blomberg, Apollos 2001, p. 91