Supervisor finished with prophet (8)
I believe the answer is:
overseer
'supervisor' is the definition.
(an overseer supervises others)
'finished with prophet' is the wordplay.
'finished' becomes 'over' (over can mean finished or ended).
'with' means one lot of letters go next to another.
'prophet' becomes 'seer' (both can mean someone who tells the future).
'over'+'seer'='OVERSEER'
(Other definitions for overseer that I've seen before include "who is put in charge" , "Person supervising" , "Supervisor or foreman" , "monitor" , "One manages" .)