One of the repeated rhetorical strategies Douglass employs is the Enlightenment "buzz words" of light and dark.
Enlightment thinkers valued reason above all else. Reason brought "light" to dark prejudices, myths, and superstitions. Slaveholders rejected reason even when presented with overwhelming "light" of the human dignity and human rights. For example, he accuses Garrison of trying to "banish all light and knowledge" and Douglass often says that "slaveholders have a hatred of the light."
Futhermore, when Douglass speaks of his mother's personal darkness, he says that she was "kept in the dark both literally and figuratively as a child." He continues, "I do not recollect ever seeing my mother by the light of day. She was with me in the night."
Douglass also rhetorcially employs biblical language and imagery to show how the "fruit" of knowledge is denied to black people. Describing his plantation, he writes, "the garden...abounded in fruits of almost every description, from the hardy apple of the north" (*the "north" itself represents freedom and knowledge). Another passage notes that the plantation's "excellent fruit was quite a temptstion to the hungry swarm of boys, as well as the older slaves." The desire for knowledge, Douglass argues, is lifelong.
Douglass's use of parallel construction, elevated writing style, and erudite word choice establish his crediblity (ethos) to the educated Abolitionist audience he is addressing in this narrative. Educated audiences knows he is self-educated, and his stylistic sophistication not only impresses them but makes it natural for them to identify with him and see beyond their racial and social differences.
While Douglass's formal diction and syntax create an emotional distance for the modern reader, his use of images and detail in Aunt Hester's beating elicit pathos even in this generation: her nakedness, her stretched arms, her having to stand on her toes while being brutally whipped, her shrieks, and the "warm blood" dripping on the floor help him emotionally engage both his original audinece and today's reader.