Emily Brent's line, "Those whom the gods would destroy..." is from the Greek dramatist Euripides. "The wicked flee . . ." is from the Book of Proverbs.
This movie, as all existent versions of "Ten Little Indians," is based not on the novel by Agatha Christie but on her very similar play. While the identity of the murderer is the same in both versions, the outcome of who survives the murderer's plot is very different.