Member of a sect opposing the Sadducees in the Bible (8)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
pharisee
(Other definitions for pharisee that I've seen before include "Ancient Jewish sectarian" , "hypocritical type" , "Ancient Jew" , "Hypocritical Biblical official" , "Member of ancient Jewish sect; Heap, sire (anag.)" .)