Image of Christ in church house concealed by extremely eccentric doctor (4,4)
I believe the answer is:
ecce homo
'image of christ in church' is the definition.
The definition suggests a singular noun which matches the answer.
'house concealed by extremely eccentric doctor' is the wordplay.
'house' becomes 'ho' (abbreviation for house).
'concealed by' indicates putting letters inside.
'extremely eccentric' becomes 'ecce' (I can't justify this - if you can you should give a lot more credence to this answer).
'doctor' becomes 'mo' (medical officer).
'ecce'+'mo'='eccemo'
'ho' inserted inside 'eccemo' is 'ECCE HOMO'.
Can you help me to learn more?
(Other definitions for ecce homo that I've seen before include "Behold the man - Latin words spoken by Pontius Pilate" , "Painting of Christ with the crown of thorns" , "picture of Christ" .)