Small church accommodating border plan (6)
I believe the answer is:
scheme
'plan' is the definition.
(scheme is a kind of plan)
'small church accommodating border' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'church' becomes 'ce' (Church of England).
'accommodating' indicates putting letters inside.
'border' becomes 'hem' (I've seen this before).
'ce' enclosing 'hem' is 'cheme'.
's'+'cheme'='SCHEME'
(Other definitions for scheme that I've seen before include "Systematic plan, plot" , "Plan (maybe best laid?)" , "Conspire" , "Project or strategy" , "Cunning plan" .)