Kray twin covers £1 debts belonging to the church (9)
I believe the answer is:
religious
'the church' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'kray twin covers ps1 debts belonging' is the wordplay.
I cannot quite see how this works, but
'debts' could be 'ious' (promises to pay debts) and 'ious' is located in the answer.
This may be the basis of the clue (or it may be nonsense).
'to' is the link.
Can you help me to learn more?
(Other definitions for religious that I've seen before include "Believing in god" , "Pious, devout" , "Strict" , "Fussy" , "Holy" .)