Composer not at home with one idol worshipper (5)
I believe the answer is:
pagan
'worshipper' is the definition.
(I know that pagan is a type of worshipper)
'composer not at home with one idol' is the wordplay.
I cannot quite see how this works, but
'one' could be 'an' (an apple is one apple) and 'an' is located in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for pagan that I've seen before include "Unbeliever" , "Heathen; non-believer" , "Infidel" , "advocate of pleasures" , "One who follows a polytheistic or pre-Christian religion, but not a Jew" .)