Note change in book for the church (7)
I believe the answer is:
psalter
'book for the church' is the definition.
I can't judge whether this defines the answer.
'note change' is the wordplay.
'note' becomes 'ps' (a PS is a note added to the end of a letter).
'change' becomes 'alter' (synonyms).
'ps'+'alter'='PSALTER'
'in' is the link.
Can you help me to learn more?
(Other definitions for psalter that I've seen before include "Book for church use" , "Book of religious songs" , "Cherub-like" , "Book used in church" , "Book of sacred songs" .)