In the story, Faulkner foreshadows Miss Emily's demise and a future in which she becomes mad. In the passage below, after experiencing a smell coming from Miss Emily's house, the townspeople recall how Miss Emily's great-aunt had gone mad:
That was when people had begun to feel really sorry for her. People in our town, remembering how old lady Wyatt, her great-aunt, had gone completely crazy at last, believed that the Griersons held themselves a little too high for what they really were.
The fact that people feel sorry for Miss Emily already suggests that they might believe she is going mad. The townspeople's recollection of Miss Emily's great-aunt shows that even people of high prestige are susceptible to madness. Further, the townspeople view the Griersons as people built of the same material. Indeed, it is because of Miss Emily's father that she does not have to pay taxes. Thus it is not a jump to believe that Miss Emily might face the same fate as her great-aunt.
Another instance of foreshadowing is when Miss Emily goes to buy arsenic. At the time, Miss Emily is described as “thinner than usual, with cold, haughty black eyes in a face the flesh of which was strained across the temples and about the eyesockets as you imagine a lighthousekeeper’s face ought to look.” From her "cold, haughty black eyes," it is suggested that Miss Emily is not in the relationship for love—only that she cannot bear for Homer to leave her. Her fear of being abandoned consumes her to the point that it drives her mad, shown by the fact that she is purchasing arsenic for suspicious purposes. In the second part of the quote, Miss Emily is compared to a lighthouse keeper. In history, lighthouse keepers, removed from society and often confined to their own company, have often been thought of as mad. The comparison foreshadows Miss Emily's own madness, for she has been emotionally alone and isolated in the world for a long time.
Homer Barron's death is foreshadowed largely through Miss Emily's actions and the nonlinear fashion in which the story relays them. The gradual and disordered revealing of information makes it seem as if there is often a hidden intent behind Miss Emily's actions. One example is when Miss Emily goes to buy arsenic:
Miss Emily just stared at him, her head tilted back in order to look him eye for eye, until he looked away and went and got the arsenic and wrapped it up. The Negro delivery boy brought her the package; the druggist didn't come back. When she opened the package at home there was written on the box, under the skull and bones: "for rats."
The first strange instance is that Miss Emily refuses to disclose what the arsenic is for, even though the law requires one to do so. The skull and bones, a common symbol for poison, foreshadows Homer's death. And to view this quote in its context, Miss Emily buys arsenic right after readers learn that Homer is not interested in marrying Miss Emily. That Miss Emily's acquisition of poison is preceded by Homer's lack of marriage intent brews suspicion.
Another example of Homer's death being foreshadowed is when Miss Emily buys a toilet set in silver with the initials "H.B." and a nightshirt. Again, this takes place after Homer reveals that he is not a marrying man. Thus the reader might question why Miss Emily still tries to continue seeing Homer, and even goes so far as to have Homer spend the night, implied by Miss Emily's purchases. This nightshirt foreshadows Homer's entrapment (by death), for at the end of the story, his corpse wears the same nightshirt that she had bought for him.