Left in church, my gran's upset reverend (9)
I believe the answer is:
clergyman
'reverend' is the definition.
('clergyman' can be a synonym of 'reverend')
'left in church my gran's upset' is the wordplay.
'left' becomes 'l' (common abbreviation**).
'in' indicates putting letters inside.
'church' becomes 'ce' (abbreviation for Church of England).
'upset' is an anagram indicator.
'my'+'gran'='mygran'
'mygran' with letters rearranged gives 'rgyman'.
'ce'+'rgyman'='cergyman'
'l' going within 'cergyman' is 'CLERGYMAN'.
(Other definitions for clergyman that I've seen before include "professional person" , "Church official" , "Man of the cloth" , "Ordained minister" , "Person of the cloth" .)