Angrier about Church initially roasting witch (8)
I believe the answer is:
sorcerer
'witch' is the definition.
(I know that witch can be written as sorcerer)
'angrier about church initially roasting' is the wordplay.
'angrier' becomes 'sorer' ('sore' can be similar in meaning to 'angry').
'about' means one lot of letters goes inside another.
'church' becomes 'CE' (abbreviation for Church of England).
'initially' says to take the initial letters.
The initial letter of 'roasting' is 'r'.
'ce'+'r'='cer'
'sorer' enclosing 'cer' is 'SORCERER'.
(Other definitions for sorcerer that I've seen before include "Necromancer or wizard" , "Magician aided by evil spirits" , "Male magician, wizard" , "Magician with musical apprentice" , "In stories, he has magical powers that he uses to harm others" .)