Unorthodox doctrine paid for later (2,6)

I believe the answer is:

on credit

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'paid for later' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.

'unorthodox doctrine' is the wordplay.
'unorthodox' is an anagram indicator.
'doctrine' anagrammed gives 'ON CREDIT'.

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