The most common and most likely answer to this crossword clue is the 3 plus 9 letter word NEW TESTAMENT
I've seen this crossword clue in Independent
N
E
W
T
E
S
T
A
M
E
N
T
More clues leading to the result NEW TESTAMENT
- Where Romans found ten teams — went crazy
- Man sent tweet off? Writings from much earlier
- Proof, after novel, a collection of religious books
- Matthew and others implied statement?
- Old books in will that’s changed?
- Books where reproductive organ is seen in amphibian, exotic creature
- Books we sent out with positive response time after time
- Man sent tweet spinning religious writing
- Odd statement on novel in book collection
- Sacred books we sent out, getting positive response time after time
Buddy explains!
The straight part
We know that "Books" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case books = new testament.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.