Place offering food for preacher John — without end (5)
I believe the answer is:
locus
'place' is the definition.
(I've seen this before)
'food for preacher john without end' is the wordplay.
'food for preacher john' becomes 'locust' (John the Baptist ate locusts).
'without end' means to remove the last letter.
'locust' with its last letter taken away is 'LOCUS'.
'offering' is the link.
(Other definitions for locus that I've seen before include "Spot" , "Range - place" , "place in court matters" , "Place of occurrence" , "line" .)