A Jewish religious leader (Pharisee) who privately questioned Jesus (Jn 3:1ff).  He was told unless a person is born again they can’t see the Kingdom of God.  It was explained to him how to be born again and what awaits those who do not believe.  It is possible he became a secret believer, spoke out for Jesus, and assisted at His burial (Jn 7:50, 19:38-42).

See also: believer (secret), born again, Kingdom of God, Pharisee, questions.