Scriptures record one saint taking off shortly (8)
I believe the answer is:
epistles
'scriptures' is the definition.
(the epistles are part of Christian scripture)
'record one saint taking off shortly' is the wordplay.
'record one' becomes 'epi' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'saint' becomes 'st' (abbreviation).
'taking off' becomes 'less' (less can mean take away or subtracting).
'shortly' means to remove the last letter.
'less' with its last letter taken away is 'les'.
'epi'+'st'+'les'='EPISTLES'
(Other definitions for epistles that I've seen before include "Long communications" , "It sleeps among letters of the Apostles" , "Biblical letters" , "Letters, missives" .)