Saying quiet resistance finished bishop (7)
I believe the answer is:
proverb
'saying' is the definition.
(I know that proverb is a type of saying)
'quiet resistance finished bishop' is the wordplay.
'quiet' becomes 'p' (music symbol for 'piano', ie soft or quiet).
'resistance' becomes 'r' (electronics abbreviation).
'finished' becomes 'over' (over can mean finished or ended).
'bishop' becomes 'B' (chess abbreviation).
'p'+'r'+'over'+'b'='PROVERB'
(Other definitions for proverb that I've seen before include "Traditional saying" , "Maxim" , "Saying encapsulating a general truth" , "Aphorism" , "'Adage, saw (7)'" .)