Saint troubled with mortal sin, leading to inappropriate conversion? (14)

I believe the answer is:

mistranslation

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'inappropriate conversion?' is the definition.
The definition and answer can be both related to communication as well as being singular nouns.
Maybe there's an association between them I don't understand?

'saint troubled with mortal sin leading' is the wordplay.
'troubled with' is an anagram indicator.
'leading' means one lot of letters go next to another.
'mortal' put after 'sin' is 'sinmortal'.
'saint' mixed up with 'sinmortal' can make 'MISTRANSLATION'.

'to' is the link.

Can you help me to learn more?

I've seen this clue in The Times.

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