Stop talking twice before work's close (4,2,4)
I believe the answer is:
shut up shop
'close' is the definition.
(thesaurus)
'stop talking twice before work's' is the wordplay.
'stop talking' becomes 'shutup' (I've seen this before).
'twice' becomes 'sh' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'before' is a charade indicator (letters next to each other).
'work' becomes 'op' (abbreviation for opus).
'shutup'+'sh'+'op'='SHUT UP SHOP'
(Other definitions for shut up shop that I've seen before include "Cease trading" , "Close business at end of day (or permanently)" .)