Certainly the introductory paragraph of this great story is essential in establishing something of the mood in this story of innocence and maturity. This is achieved mainly through the personification that is employed in describing the house on the narrator's dead-end street:
North Richmond Street, being blind, was a quiet street except at the hour when the Christian Brothers' School set the boys free. An uninhabited house of two stories stood at the blind end, detached from its neighbours in a square ground. The other houses of the street, conscious of decent lives within them, gazed at one another with brown imperturbable faces.
Note how the diction employed in this paragraph, in particular the words "conscious," "gazed," and "imperturbable faces" combine to create a somewhat ominous and gloomy atmosphere as the houses are described as faces looking out without expression. Note how this mood is sustained in the following paragraphs through the use of such words as "sombre," "musty," "damp," "muddy," "dark" and feeble."
All of these effects serve to create a somewhat restricted atmosphere in which the characters are trapped in their gloomy and oppressive lives and routines. In the quote above we have the example of the school "setting the children free." Thus we can understand the attraction of the boy to the word "Araby" with all of its promise of mystery, gold and exoticism, linked to his attraction to Mangan's sister.