Disclosure that the vicar has high spirits (10)
I believe the answer is:
revelation
'disclosure' is the definition.
('revelation' can be a synonym of 'disclosure')
'the vicar has high spirits' is the wordplay.
'the vicar' becomes 'rev'.
'has' means one lot of letters go next to another.
'high spirits' becomes 'elation' ('elation' can be a synonym of 'high spirits').
'rev'+'elation'='REVELATION'
'that' is the link.
(Other definitions for revelation that I've seen before include "Extraordinary event" , "telling statement" , "Part of Bible" , "unexpected display" , "enlightening experience" .)