Behold the end of messy religious disagreement? (6)
I believe the answer is:
heresy
'religious disagreement?' is the definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
'behold the end of messy' is the wordplay.
'behold' becomes 'here' (I can't explain this - if you can you should give a lot more credence to this answer).
'the end of' says to hollow out the word (remove centre letters) (I've seen 'ends of' mean this).
'messy' becomes 'sloppy' (I've seen this before).
'sloppy' with its centre taken out is 'sy'.
'here'+'sy'='HERESY'
Can you help me to learn more?
(Other definitions for heresy that I've seen before include "Unorthodox religious belief" , "Deviation from orthodox religious thinking" , "unorthodox views" , "Unorthodox view" , "Belief that's anathema to the orthodox" .)