Before noon I hear you permitted this protective charm (6)
I believe the answer is:
amulet
'protective charm' is the definition.
(I've seen this in another clue)
'before noon i hear you permitted' is the wordplay.
'before noon' becomes 'AM' (as in AM on a clock).
'i hear' indicates a 'sounds like' (homophone) clue.
'permitted' becomes 'let' (to let something happen is to permit it).
'you' sounds like 'u'.
'am'+'u'+'let'='AMULET'
'this' acts as a link.
(Other definitions for amulet that I've seen before include "Thing worn as charm against evil" , "Charm worn to ward off evil" , "Lucky ornament" , "Jewel to protect from witchcraft" , "Ornament thought to give protection" .)