Criminal serves sandwiches quietly for evening gathering at church (7)
I believe the answer is:
vespers
'church' is the definition.
(thesaurus)
'criminal serves sandwiches quietly' is the wordplay.
'criminal' indicates anagramming the letters.
'sandwiches' is an insertion indicator (goes on either side like a sandwich).
'quietly' becomes 'p' (p for piano and quiet).
'serves' with letters rearranged gives 'vesers'.
'vesers' going around 'p' is 'VESPERS'.
'for evening gathering at' is the link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for vespers that I've seen before include "Evensong - RC service" , "Evening prayers" , "Evening service" , "An hour of worship" .)