Repellent Tory goes off parts of a church service (8)

I believe the answer is:

nocturns

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'parts of a church service' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'repellent tory goes off' is the wordplay.
'repellent' becomes 'no' (I can't justify this - if you can you should give a lot more credence to this answer).
'tory' becomes 'c'.
'goes off' becomes 'turns' (I've seen this before).
'no'+'c'+'turns'='NOCTURNS'

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I've seen this clue in The Independent.

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