Filthy pen for a miscreant (7)

I believe the answer is:

profane

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'filthy pen for a miscreant' is the definition.
I can't judge whether this defines the answer.

'filthy pen for a' is the wordplay.
'filthy' is an anagram indicator (messy letters).
'pen'+'for'+'a'='penfora'
'penfora' with letters rearranged gives 'PROFANE'.

Can you help me to learn more?

(Other definitions for profane that I've seen before include "(Of language) blasphemous" , "Sacrilegious or blasphemous" , "Contemptuous of sacred things" , "Unholy" , "Treat with irreverence" .)

I've seen this clue in the Sydney Morning Herald.

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