Character from "Small Gods" by Terry Pratchett.
I read it in Finnish so I could get some of the titles wrong but he was basically the Grand Inquisitor (or actually Exquisitor or something) of a highly militant religion not entirely unlike Catholism during its worst times.
Vorbis is a character who is considered to be the obvious candidate for the next "Pope" (Prophet I think the title was) of the religion due to his devotion to the religion and his task of torturing unbelievers and heretics. Vorbis is a liar, a cruel sociopath who starts wars while pretending to be diplomatic and posing as a victim. ...He also lacks faith completely. He IS loyal to the cause of the religious organization but seems to utterly lack any faith in their god and merely goes with the rules for the sake of rules and to gain power for himself.