Unothodox doctrine, with payment deferred (2,6)

I believe the answer is:

on credit

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'payment deferred' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.

'unothodox doctrine' is the wordplay.
'doctrine' anagrams to 'ON CREDIT'.
But, I am not sure how this is indicated.

'with' acts as a link.

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