Self-righteous at church surrounded by saints and stars (6)
I believe the answer is:
pisces
'stars' is the definition.
(I know that Pisces is a constellation)
'self-righteous at church surrounded by saints' is the wordplay.
'self-righteous' becomes 'pi' (pi is an old-fashioned slang term for pious).
'at' says to put letters next to each other.
'church' becomes 'CE' (abbreviation for Church of England).
'surrounded by' means one lot of letters goes inside another.
'saints' becomes 'ss' (an abbreviation for saint written twice).
'ce' going into 'ss' is 'sces'.
'pi'+'sces'='PISCES'
'and' acts as a link.
(Other definitions for pisces that I've seen before include "stars" , "Twelfth sign of the zodiac, the Fish" , "Spice for the Fish" , "Fish star sign" , "'Sign of the zodiac, the fish (6)'" .)