Painter Peter Paul (6)
I believe the answer is:
rubens
'painter peter paul' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for rubens that I've seen before include "Flemish painter, knighted by Charles I in 1629" , "Flemish baroque artist" , "Peter Paul -, sixteenth to seventeenth century Flemish painter" , "Burnes turns out to be an artist" , "Sir Peter Paul ---, painter" .)