Model to preface book (9)

I believe the answer is:

precedent

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'model' is the definition.
(I've seen this before)

'preface book' is the wordplay.
'preface' becomes 'precede' (I can't explain this - if you can you should believe this answer much more).
'book' becomes 'NT' (New Testament).
'precede'+'nt'='PRECEDENT'

'to' acts as a link.

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(Other definitions for precedent that I've seen before include "model" , "Example to follow" , "Herald" , "Past instance serving as example" , "Earlier parallel event" .)

I've seen this clue in The Daily Express.

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