Outdo former church leader in local (5)
I believe the answer is:
excel
'outdo' is the definition.
(I've seen this before)
'former church leader in local' is the wordplay.
'former' becomes 'ex'.
'church' becomes 'ce' (abbreviation for Church of England).
'leader in' suggests taking the first letters.
The initial letter of 'local' is 'l'.
'ex'+'ce'+'l'='EXCEL'
(Other definitions for excel that I've seen before include "Eclipse" , "Perform extremely well" , "Be the best" , "Be outstanding" , "Be pre-eminent" .)