Devotee inhabits safety location in retreat (7)
I believe the answer is:
acolyte
'devotee' is the definition.
(I've seen this in another clue)
'inhabits safety location in retreat' is the wordplay.
'inhabits' indicates the answer is hidden within the clue (I've seen 'inhabiting' mean this).
'in retreat' says the letters should be written backwards.
'etyloca' is hidden within 'safety location'.
'etyloca' backwards is 'ACOLYTE'.
(Other definitions for acolyte that I've seen before include "Loyal follower" , "Altar boy" , "trainee" , "Person who assists a priest" , "Adherent or priest's assistant" .)