Judaism
From Tardis Wiki, the free Doctor Who reference
Judaism was one of the major religions of Earth and was practiced by the Jewish people.
When Christianity came into being the Jews leaders - in particular the Pharisees - reacted with hostility. They tired to murder Lazarus and any one else they judged to have had contact with Jesus Christ. (PDA: Byzantium!)
I have no doubt that they, the Jews that is, consider Christianity to be a danger to them.
Judaism was the precursor to "New Judaism." The Tenth Doctor asked the Beast, if he was the Devil of New Judaism, along with that of numerous other religions, to which he responded he was the Devil of all religions. (DW: The Satan Pit)