Turn over books penned by judge (6)
I believe the answer is:
rotate
'turn over' is the definition.
(thesaurus)
'books penned by judge' is the wordplay.
'books' becomes 'ot' (Old Testament).
'penned by' is an insertion indicator.
'judge' becomes 'rate' (rating is a kind of judging**).
'ot' going inside 'rate' is 'ROTATE'.
(Other definitions for rotate that I've seen before include "Whisk round" , "Turn around as on axle or spit" , "Spin as on axle" , "Make to spin around" , "Revolve" .)