Crossword Genius

Religious belief set him off (6)

Ross

I believe the answer is:

theism

'religious belief' is the definition.
(theism is a kind of religious belief)

'set him off' is the wordplay.
'off' is an anagram indicator.
'set'+'him'='sethim'
'sethim' with letters rearranged gives 'THEISM'.

(Other definitions for theism that I've seen before include "of faith" , "Belief in existence of a God revealed to man" , "The doctrine or belief in the existence of a God or gods" , "Belief in a creator" , "Belief in a deity" .)

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