How are sound devices connected to the word "black" in the latter part of Rev. Bsrbee's sermon in Invisible Man

The event at chapel which affects the narrator most is the speech of the Reverend Barbee. The narrator touches on "dark" imagery" such as a dark conspiracy, a funeral procession, and the journey underground. Another clue of this man falling into a pattern of the narrator's life is the dark-glasses the reverend "hides" behind, a notion which will surface in later chapters. Certainly "black " is also important in the fact that he is hiding his blindness behind the glasses while creating an illusion for the audience to see into and believe.