Wordage of law written by church figure (7)
I believe the answer is:
lexicon
'wordage' is the definition.
(thesaurus)
'law written by church figure' is the wordplay.
'law' becomes 'lex' (Latin for 'law').
'written by church figure' becomes 'icon' (I can't explain this - if you can you should give a lot more credence to this answer).
'lex'+'icon'='LEXICON'
'of' acts as a link.
Can you help me to learn more?
(Other definitions for lexicon that I've seen before include "Wordbook" , "Vocabulary - dictionary" , "(Classical) dictionary" , "set of terms" , "Word reference book" .)