Telling crook about books (probably stolen) (3-6)
I believe the answer is:
ill-gotten
'probably stolen' is the definition.
(as in ill-gotten goods)
'telling crook about books' is the wordplay.
'crook' indicates anagramming the letters (a crooked or broken form of the letters).
'about' indicates putting letters inside.
'books' becomes 'ot' (Old Testament).
'telling' with letters rearranged gives 'illgten'.
'illgten' placed around 'ot' is 'ILL-GOTTEN'.
(Other definitions for ill-gotten that I've seen before include "Obtained dishonestly" , "Obtained wrongly or criminally - give telling to" , "These gains are obtained by unlawful means" , "These gains are through evil or unlawful means" , "These gains are dishonestly come by" .)