Just to add to the cogent details already mentioned in Post #4, there is much significance to the books that the boy discovers in the priest's room. The Abbot by Sir Walter Scott idealizes Mary Queen of Scots, who was less that an examplarary Catholic, The Memoirs ofVidocq is a popular account of the exploits of a criminal turned detective; the novel is a blend of invention, sensationalism, and prurience--all but one are odd books for a priest to have read. These suggest, too, the boy's confusion of the religious fervor, idealism, and sexual attraction in his infatuation with Mangan's sister.
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The boy’s biblical and holy descriptions of the setting and Magan’s sister enhance his sacred adoration toward her which ultimately leads him through maturation from a boy to a man. To the boy, the girl is saintly and angelic; she is always surrounded by “light”, as if by a halo. She becomes an object of faith to the boy and when she finally talks to him the light “[catches] the white curve of her neck, [lights] her hair… [and] the hand”. When she tells him how she wishes to go to the Araby, he promises he will “bring something back”. He imagines himself as a knight in search of the Holy Grail and his trip to the Araby is to him a holy crusade. The bazaar is filled with “darkness” and “silence” which he describes as an enchanted “church after a service”. Yet, as the Holy Grail was never found, the boy realizes at the bazaar that his love is not to be found. Through such realization, the boy takes his first step to adulthood.
The blind North Richmond Street, a cul de sac, with an uninhabited house at its blind end, which is the immediate setting must be a metaphor of the 'blind alley' that our lived existence is in a big city. Then we have the unkempt garden with the central apple tree and irregularly growing bushes, suggesting a lost Eden, having lost its Adam in the dead priest. The dark muddy lanes, the dark gardens co-existing with the ashpits and stables, the flaring streets and noisy market-place on Saturday evenings further contribute to the setting of drab, routine city life. The cold, empty, silent rooms in the boy's house in contrast to the dining-hall and the front parlour, the cold wind, the rains, the boy's late walk along the busy festive streets towards Araby and the nearly dark fair-ground where the boy discovers the futility of his search for the beautiful-all are very important elements of the story's setting.
The setting of the story changes from the "blind" neighborhood, "musty" articles, and shady circumstances. It moves to the subway, which tries to prevent him from achieving his prize, to finally, Araby, the tacky market, in the form of an illusionary foreign adventure.