How can we explain Faulkner's use of time in "The Sound and the Fury"?
Time in this novel is both a stylistic device and a theme. Faulkner uses it stylistically in telling the narrative. Both Benjy and Quentin move backward and forward in time in their own heads, being plagued by memory. This causes flashbacks that interrupt the narrative flow of the novel. It is worse in Benjy's section because he confuses his memory for his present, making the "switches" seamless and hard to follow. For Quentin, he is more coherent, more focused on the impact of time, so his flashbacks are better transitioned. Finally, there is Jason, who lives in the present, making his section the most chronologically told. As he is unconcerned with the past, there are no flashbacks.
By using this technique, Faulkner is able to highlight time as a theme, portraying its effect on humanity in three different ways. Time weighs on all of us and is the measurement of life as we pass through it. For Benjy, he is not capable of recognizing time's passage, and so moves back and forth in it as his mind flits across his memories. For Quentin, he is so distraught by the weight of the time that has passed - and what he has lost - that he is equally disabled. He gets stuck in the past, and overwhelmed by the time, and can not live. For Jason, he is so ignorant of time's passage that he can not look back and learn from his mistakes, or from humanity in general.