I think William Faulkner begins his novel The Sound and the Fury with Benjy Compson as the narrator because it reveals the true nature of all the characters. The narrative is quite disoriented, and it's difficult to distinguish the present from the past; however, this is how the reader is introduced to Benjy's mind. Benjy is extremely handicap, with obviously no concept of time. His narration allows the reader to get a glimpse of what is really going on in his mind. Also, it lets the reader see the real personalities of all the characters before they have a chance to introduce themselves in their own chapters. This hints to the reader that Benjy's interpretation of situations throughout the novel is the most accurate because he is the most observant and the most innocent, having nothing to hide, which again proves that he says it how it is.
In the Compson household, Benjy seems to be emotionally neglected by almost everyone except Caddy. For example, Benjy's original name was Maury, after Uncle Maury. However, after the family found out that Maury had a mental retardation, they changed his name to Benjy. This seems odd, since by this time, he was already 6 or 7 years old. It didn't matter to the family because leaving his name as Maury would be a dishonor to the family, especially Uncle Maury. In general, Benjy seems to be a burden on the family; Luster even claims that if Caroline Compson, his mother, were to die, his father would send him off to the insane asylum.
In this chapter, the date is said to be the Saturday before Easter Sunday, and Benjy is 33, the age of Jesus when he was crucified. I haven't read on yet, but after learning this, I originally assumed it was foreshadowing for Benjy's death. But then I learned that really Benjy suffers everyday at the hands of the people he loves unconditionally, like Jesus did. Benjy hasn't done anything for people to dislike him, he was just born that way.
Benjy also seems to live a lot in the past, due to his countless sporadic memories. I think he recalls so much from the past because people tend to love the past when their present isn't as satisfying. In his past, Benjy had Caddy, who obviously loved him the most and made an effort to show it. Now, with her off and married, Benjy's present isn't as lively, and mostly dark from outside hatred. Also, the older he gets, the more judgmental people of the South seem to become because they expect more from a man, but little do they understand that he still hasn't matured as much mentally. When they see an adult man acting the way he does, they're more appalled. When Benjy acted the same way as a child, it wasn't as noticeable, so to say, because he was still a kid. Adult men need to control their sexual impulses, as Mrs. Oles mentioned, and it's clear that Benjy isn't mature enough to do so yet. However, he is still a 33 year old man, so what he does now can be seen differently from what he was doing as a child, although the actions are the same, despite age. Adults are held to a different standard than children, and that goes for every society, not just that found in the South during that time.
In the novel, Benjy Compson is the most innocent character, which says that his narration is the most true because he sees everything through "unfiltered" eyes--he doesn't choose what to see or ignore, he sees it all. He is also persecuted daily for who he is, although he didn't choose his lifestyle. But this doesn't affect how he feels about others, because due to his innocence, it seems that he still loves everyone unconditionally. This behavior closely resembles Jesus, who Benjy could easily represent in the novel. This God-like character symbolizes innocence in Faulkner's narrative.