Clever of bishop to drink beer? Just the opposite! (4)
I believe the answer is:
able
'clever' is the definition.
(thesaurus)
'bishop to drink beer? just the opposite' is the wordplay.
I cannot quite understand how this works, but
'bishop' could be 'b' (abbreviation used in chess) and 'b' is found in the answer.
'drink' could be 'ale' (I've seen this before) and 'ale' is found within the remaining letters.
No letters remain.
This may be the basis of clue (or it may be nonsense).
'of' acts as a link.
(Other definitions for able that I've seen before include "Fit as a seaman" , "Competent as, say, sailor" , "Adept" , "Competent and equipped" , "See 10" .)