Punishment for sin (7)
I believe the answer is:
penance
'punishment for sin' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for penance that I've seen before include "Act imposed for sin" , "Voluntary self-abasement" , "humiliating act" , "Expression of sorrow for sin" , "Act of penitence" .)