Open-mouthed at the love feast (5)
I believe the answer is:
agape
I believe this clue is a triple definition!
'open-mouthed' is the first definition.
(I've seen this in another clue)
'at' acts as a link.
'the love' is the second definition.
(I've seen this before)
'feast' is the third definition.
(I've seen this before)
(Other definitions for agape that I've seen before include "Christian feast" , "Astonished" , "showing disbelief" , "Christian's love" , "ecclesiastical feast" .)