The narrator and Roderick Usher were friends in "early boyhood." This long lasting bond of affection colors the narrator's view of Roderick and softens him towards his old friend's odd demeanor and behavior. His sympathy towards Roderick impacts the story by encouraging the reader to feel compassion for this troubled character.
For example, on first seeing Roderick, the narrator is both convinced of his old friend's "perfect sincerity" and shocked at how much he has changed in the time since they last saw each other:
I gazed upon him with a feeling half of pity, half of awe. Surely, man had never before so terribly altered, in so brief a period, as had Roderick Usher!
It could be very easy, given a less sympathetic narrator, for the reader to find Roderick unbearably creepy, strange, or even evil. Yet this narrator responds to him as a fellow human being and shows his kindness. Despite all that has happened to Roderick, the narrator refers to him as his "friend" seven times over the course...
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