Cryptically, God in sin? (10)
I believe the answer is:
wrongdoing
'sin?' is the definition.
(sin is a kind of wrongdoing)
'cryptically god in' is the wordplay.
I cannot really see how this works, but
an anagram of 'god' is 'gdo' which is located in the answer.
'in' is within the answer.
The remaining letters 'wrong' is a valid word which might be clued in a way I don't see.
This may be the basis of clue (or it may be nonsense).
(Other definitions for wrongdoing that I've seen before include "Evil action" , "Misdeed" , "sin" , "Illegal behaviour" .)