A saint isn't a saint to blurt out ''I hold traditional Catholic belief (23)

I believe the answer is:

transubstantiationalist

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'a saint isn't a saint to blurt out ''i hold traditional catholic belief' is the definition.
I can't tell whether this definition defines the answer.

'a saint isn't a saint to blurt out' is the wordplay.
'out' indicates anagramming the letters (out can mean wrong or inaccurate).
'a'+'saint'+'isnt'+'a'+'saint'+'to'+'blurt'='asaintisntasainttoblurt'
'asaintisntasainttoblurt' anagrammed gives 'TRANSUBSTANTIATIONALIST'.

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I've seen this clue in The Times.

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