Ultra-conservative theologian takes in Ireland on the beer briefly
I believe the answer is:
die-hard
'ultra-conservative' is the definition.
(I've seen this before)
'theologian takes in ireland on the beer briefly' is the wordplay.
I cannot really understand how this works, but
'ireland' could be 'ie' (two letter country code) and 'ie' is present in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for die-hard that I've seen before include "One who won't accept novelty" , "One strongly opposed to change" , "Fanatic" , "Obstinately resistant to change" , "Strong opponent of change" .)