Priest on holiday who's sacked for toying with children (6,9)
I believe the answer is:
father christmas
'who's sacked for toying with children' is the definition.
(Father Christmas has a sack of toys for children)
'priest on holiday' is the wordplay.
'priest on' becomes 'father' (I am not sure about this - if you are sure you should believe this answer much more).
'holiday' becomes 'christmas' (Christmas is an example).
'father'+'christmas'='FATHER CHRISTMAS'
(Other definitions for father christmas that I've seen before include "Santa!" , "late December he's busy" , "man with gifts" , "present supremo" , "he'll be sacked" .)