Modest talent written about in books (3,9)
I believe the answer is:
old testament
'books' is the definition.
(books of the Bible)
'modest talent written about' is the wordplay.
'written about' is an anagram indicator (letters moved about before being rewritten).
'modest'+'talent'='modesttalent'
'modesttalent' with letters rearranged gives 'OLD TESTAMENT'.
'in' acts as a link.
(Other definitions for old testament that I've seen before include "First part of the Bible" , "Modest talent (anag.)" , "Job, for example, to be found here" , "Books" , "religious work" .)