Moralise before going to a church (6)
I believe the answer is:
preach
'moralise' is the definition.
(I've seen this before)
'before going to a church' is the wordplay.
'before' becomes 'pre'.
'going to' says to put letters next to each other.
'church' becomes 'ch' (common abbreviation**).
'pre'+'a'+'ch'='PREACH'
(Other definitions for preach that I've seen before include "Do as Amos Starkadder did" , "Evangelise" , "Give, eg, a sermon" , "Proclaim (a religious message)" , "Give moral or religious advice" .)