The blessed Guardian’s not partisan, somehow! (6,5)
I believe the answer is:
patron saint
'the blessed guardian's' is the definition.
'patron saint' can be an answer for 'guardian's' (patron saint is a kind of guardian). I'm unsure of the 'the blessed' bit.
'not partisan somehow' is the wordplay.
'somehow' is an anagram indicator.
'not'+'partisan'='notpartisan'
'notpartisan' with letters rearranged gives 'PATRON SAINT'.
Can you help me to learn more?
(Other definitions for patron saint that I've seen before include "Unearthly guardian" , "National representative" , "Patrick for Ireland, for example" , "Religious guardian" , "Holy guardian of country, trade etc" .)