Pray the change will do you good (7)
I believe the answer is:
therapy
'will do you good' is the definition.
(I've seen this before)
'pray the change' is the wordplay.
'change' is an anagram indicator.
'pray'+'the'='praythe'
'praythe' with letters rearranged gives 'THERAPY'.
(Other definitions for therapy that I've seen before include "Curative treatment" , "Remedial treatment" , "Healing treatment" , "healing process" , "Medical treatment" .)