The excerpt given above is taken from Phillis Wheatley's poem "On Being Brought from Africa to America". The word sable literally means color black. In this line, Wheatley uses the word "sable" to indicate sense of inferiority. The author is an African and their race color is different from the rest.
(sorry if im wrong)
Overall, this sentence seems correct to me.
Answer: The theme of Cinderella as told by the Brothers Grimm, is that if you have faith and are true to yourself, you can eventually get what you want.
