When the narrator opened the door the first time in "The Raven," there was no one there. The narrator was puzzled by the empty space outside his door.
The raven
The raven may be considered an agent of the supernatural because it first, according to the narrator, taps on the chamber door then on the window, but I believe the narrator "nodded, nearly napping," was unable to comprehend that the raven was tapping at the window from the beginning.
There's a tapping at the door.
In the poem "The Raven" by Edgar Allan Poe, the rapping sound first comes from the narrator's encounter with the mysterious bird that taps on his chamber door. The second time the rapping occurs, it is revealed that the sound was actually the result of the narrator's deep sorrow and internal torment, signifying his descent into madness.
The first gentle rapping at the narrator's door occurs in the eighth stanza of Edgar Allan Poe's poem "The Raven." It signifies the arrival of the mysterious visitor who turns out to be the titular bird.
the narrator hears a gentle rapping at the door.
the narrator hears someone tap on the door.
the narrator hears someone tap on the door.
In the first stanza of "The Raven," the narrator is reading a book to distract himself from his grief over the loss of Lenore. He hears a tapping at his chamber door but, when he opens it, finds nothing there. The narrator is then filled with dread as he speculates what could be causing the noise.
Rapping on the door (apex)
In Edgar Allan Poe's "The Raven," the "chamber door" symbolizes the boundary between the narrator's inner world of grief and despair and the outside world. It represents isolation, as the narrator is shut away in his chamber, consumed by sorrow over the loss of Lenore. The repeated reference to the chamber door also heightens the sense of dread and anticipation as the narrator confronts the mysterious presence of the raven, which ultimately amplifies his emotional turmoil.
"--here I opened wide the door;-- Darkness there and nothing more." Would you expect to see a black bird with that background if you were expecting a person? I think it is probable the raven was tapping at the window all along, but the first time the narrator was too sleepy to recognize the direction of that tapping.