Church service, say, not entirely debased with it (7)
I believe the answer is:
worship
'church service say' is the definition.
'not entirely debased with it' is the wordplay.
'not entirely' means to remove the last letter.
'debased' becomes 'worse'.
'with it' becomes 'hip' (I've seen this before).
'worse' with its last letter taken off is 'wors'.
'wors'+'hip'='WORSHIP'
(Other definitions for worship that I've seen before include "Offer praise to" , "religious service" , "Adoration of a divine being" , "Religious rites and ceremonies" , "Devotions" .)