Two support the Church (5)
I believe the answer is:
brace
'two' is the definition.
(brace is a kind of two)
'support the church' is the wordplay.
'support' becomes 'bra' (a support for the breasts).
'the church' becomes 'ce' (abbreviation for Church of England**).
'bra'+'ce'='BRACE'
(Other definitions for brace that I've seen before include "Tighten, strengthen" , "Support; two" , "prepare for impact" , "Support - couple" , "Strengthening piece" .)