Collapse in congregation? (4)
I believe the answer is:
fold
I believe this is a double definition.
'collapse' is the first definition.
(thesaurus)
'congregation?' is the second definition.
('fold' can be a synonym of 'congregation')
'in' is the link.
(Other definitions for fold that I've seen before include "enclosure" , "Members of church" , "Pleat; sheep pen" , "Gather < church" , "Tuck - pen" .)