Why is the quote, "I bore my chalice safely through a throng of foes," significant and what literary device does it show?

He is in the middle of the marketplace where he and his aunt are walking "through the flaring streets, jostled by drunken men and bargaining women, amid the curses of labourers, the shrill litanies of shop-boys."  These types of people are considered sinners.  From the beginning of the story, Joyce makes the boy out to be some religious hero who will save and win over the perfect girl.  The theme of religion is sprinkled throughout the text. The books he holds most dear were left there from the priest who lived there before he did.  When Mangan's sister leaves, she is going on a religious retreat of some sort.  Even Araby is a "church-sponsered bazaar."

This quote is significant because it's at the beginning when he sees himself as this religious hero.  He's making his way through the "throng of foes" who are the sinners.  His "chalice" is he himself and his innocence. This is simply a metaphor showing how he must be strong to make it through such a rough place without getting "dirty."