Quiet diocese in which set of holy books is put forward (7)
I believe the answer is:
promote
'is put forward' is the definition.
(thesaurus)
'quiet diocese in which set of holy books' is the wordplay.
'quiet' becomes 'p' (music symbol for 'piano').
'diocese' becomes 'rome' (Rome is an example).
'in which' is an insertion indicator.
'set of holy books' becomes 'ot' (abbreviation for Old Testament).
'rome' placed around 'ot' is 'romote'.
'p'+'romote'='PROMOTE'
(Other definitions for promote that I've seen before include "Encourage - upgrade" , "Raise to a more senior position" , "Move up -- market" , "Raise to a higher position -- advertise" , "Actively support" .)