Devoted theologian drinking a brew of iced tea (9)
I believe the answer is:
dedicated
'devoted' is the definition.
('dedicated' can be a synonym of 'devoted')
'theologian drinking a brew of iced tea' is the wordplay.
'theologian' becomes 'dd' (Doctor of Divinity degree).
'drinking' indicates putting letters inside.
'a brew of' is an anagram indicator (I've seen this in other clues).
'iced'+'tea'='icedtea'
'icedtea' anagrammed gives 'edicate'.
'dd' placed around 'edicate' is 'DEDICATED'.
(Other definitions for dedicated that I've seen before include "Committed" , "Customised" , "Devoted to a cause or ideal 99)" , "Diligent" , "exclusive" .)