Intact Bible books found in Ireland (6)
I believe the answer is:
entire
'intact' is the definition.
(synonyms)
'books found in ireland' is the wordplay.
'books' becomes 'NT' (New Testament).
'found in' indicates putting letters inside.
'ireland' becomes 'eire' (poetic name for Ireland).
'nt' going into 'eire' is 'ENTIRE'.
'bible' is the link.
I am not very happy about this link. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for entire that I've seen before include "Unharmed - total" , "outright" , "Full, intact" , "everything" , "Utter" .)