Religious observance is not at fault, by the sound of it (4)
I believe the answer is:
rite
'religious observance' is the definition.
(I've seen this in another clue)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for rite that I've seen before include "Tries awkwardly to perform rituals" , "(Words used in) ceremonial" , "Formal procedure" , "Uncomplaining person" , "Solemn ceremony" .)