Famous books in revolutionary study (5)
I believe the answer is:
noted
'famous' is the definition.
(noted can mean well-known or famous)
'books in revolutionary study' is the wordplay.
'books' becomes 'OT' (Old Testament).
'in' means one lot of letters goes inside another.
'revolutionary' is a reversal indicator.
'study' becomes 'den' (term for a study or office).
'den' backwards is 'ned'.
'ot' going within 'ned' is 'NOTED'.
(Other definitions for noted that I've seen before include "Celebrated or recorded" , "Made a record - celebrated" , "Recorded; famous" , "Widely known and esteemed" , "Celebrated, eminent" .)