Knock back drink in old church and head for bishop's office (10)
I believe the answer is:
episcopate
'bishop's office' is the definition.
(I've seen this before)
'knock back drink in old church and head' is the wordplay.
I cannot really understand how this works, but
'knock' could be 'pat' (I've seen this in other clues) and 'pat' is located in the answer.
'old' could be 'o' (common abbreviation eg in OE for Old English) and 'o' is located in the answer.
'church' could be 'ce' (abbreviation for Church of England) and 'ce' is present in the leftover letters.
This explanation may well be incorrect...
'for' acts as a link.
Can you help me to learn more?
(Other definitions for episcopate that I've seen before include "bishop's office" , "See" , "clergyman's office" , "Bishopric" .)