Profane brat promises to achieve redemption (7)
I believe the answer is:
impious
'profane' is the definition.
(associated in meaning)
'brat promises to achieve redemption' is the wordplay.
I cannot really understand how this works, but
'brat' could be 'imp' (I've seen this in another clue) and 'imp' is located in the answer.
'promises' could be 'ious' (promises to pay a debt) and 'ious' is found in the answer.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for impious that I've seen before include "Lacking reverence for God" , "9 [DEMON]" , "Wicked, profane" , "Showing disrespect for a god" , "Lacking veneration or respect" .)