Look to burn church (6)
I believe the answer is:
search
'look' is the definition.
(I know that look can be written as search)
'burn church' is the wordplay.
'burn' becomes 'sear' (sear can mean to burn).
'church' becomes 'ch' (common abbreviation).
'sear'+'ch'='SEARCH'
'to' acts as a link.
(Other definitions for search that I've seen before include "Examine (to find something)" , "Frisk" , "Look carefully (for)" , "Chaser (anag)" , "Ransack" .)