Forcefully reprimanded aide that rector foolishly employed (4,3,4,3)
I believe the answer is:
read the riot act
'forcefully reprimanded' is the definition.
(to read someone the riot act is to discipline them)
'aide that rector foolishly employed' is the wordplay.
'foolishly employed' indicates an anagram (letters in a foolish order).
'aide'+'that'+'rector'='aidethatrector'
'aidethatrector' anagrammed gives 'READ THE RIOT ACT'.
(Other definitions for read the riot act that I've seen before include "severe warning" , "Wag one's finger" .)