Contradict most of religious doctrine (5)
I believe the answer is:
belie
'contradict' is the definition.
('belie' can be a synonym of 'contradict')
'most of religious doctrine' is the wordplay.
'most of' means to remove the last letter.
'religious doctrine' becomes 'belief' (belief is a kind of religious doctrine).
'belief' with its final letter taken away is 'BELIE'.
(Other definitions for belie that I've seen before include "Fail to justify" , "Contradict" , "Confute" , "Show to be untrue" .)