The opening paragraph describes the street that the narrator lives on. North Richmond Street is "blind" indicating that in its isolated world, it (personified) can't see beyond its own confines. The houses themselves are personified, giving the town a sense of its own closed off existence:
The other houses of the street, conscious of decent lives within them, gazed at one another with brown imperturbable faces.
This initial setting of these houses with their brown, imperturbable (calm or unable to be excited) faces suggests a stagnant atmosphere. The narrator then remarks that he found books, owned by the former tenant of his own home, and his interest in literature suggests an interest in mental escape. The opening paragraph describes the setting from which he wants to escape or at least make his life there more significant.
Despite this drab description of the initial scene, the narrator does describe a playful childhood there. But his play is structured around other potential discoveries or epiphanies. He would watch Mangan's door to catch a glimpse of his sister. The narrator, in his mental escape, imagines himself as a knight performing spiritual and romantic quests for Mangan's sister. This is also why he goes to Araby to buy her something. Even in the most mundane chores, the narrator imagines he is on some quest:
These noises converged in a single sensation of life for me: I imagined that I bore my chalice safely through a throng of foes. Her name sprang to my lips at moments in strange prayers and praises which I myself did not understand.