Part of church left following risk (7)
I believe the answer is:
chancel
'part of church' is the definition.
('chancel' is part of 'church')
'left following risk' is the wordplay.
'left' becomes 'l' (common abbreviation).
'following' means one lot of letters go next to another.
'risk' becomes 'chance' ('chance' can be a synonym of 'risk').
'l' after 'chance' is 'CHANCEL'.
(Other definitions for chancel that I've seen before include "Part of church containing altar" , "Part of church near altar" , "choir and clergy's area" , "screened-off area" , "Area around the altar of a church" .)