Founder of monastic order revered in Spain (9)
I believe the answer is:
augustine
'founder of monastic order' is the definition.
(St Augustine founded a monastic order)
'revered in spain' is the wordplay.
'revered' becomes 'august' (synonyms).
'spain' becomes 'e' (abbreviation for Espana).
'august'+'in'+'e'='AUGUSTINE'
(Other definitions for augustine that I've seen before include "Friar" , "Missionary" , "First Archbishop of Canterbury" , "Saint" .)