Describe Miss Emily's house by the time of her death.
Before her death, Miss Emily stopped giving painting lessons at her house, and she essentially closed it off to everyone except for herself and her servant.
By the time of her death, Emily's house is in a state of utter decay, and as such it functions as a symbol of the dying traditions she had clung to in her life.
Let's take a look at some details that show how shabby, dusty, and dilapidated Emily's home had become:
1. "Now and then we would see her in one of the downstairs windows--she had evidently shut up the top floor of the house--..."
The fact that Emily seems to have closed off the entire upper level before her death reveals that the home is "dying," or that it's in a state of disuse. Of course, we find out later that she was--brace yourself--keeping the dead body of her lover upstairs, so the upper level was quite literally a place for the dead.
2. "And so she died. Fell ill in the house filled with dust and shadows..."
Here we see that "dust and shadows" pervaded her home. Both dust and shadows are remnants or vestiges of what is no longer in existence, so they're appropriate symbols for the dying Southern ideals that Emily struggled to hold onto.
3. "She died in one of the downstairs rooms, in a heavy walnut bed with a curtain, her gray head propped on a pillow yellow and moldy with age and lack of sunlight."
The "yellow and moldy" pillow is, we're told, is not just old but has also been kept in the dark.
4. "A thin, acrid pall as of the tomb seemed to lie everywhere upon this room ... upon the valance curtains of faded rose color, ... the man's toilet things backed with tarnished silver, ... a collar and tie, as if they had just been removed, which, lifted, left upon the surface a pale crescent in the dust."
Above are the most relevant parts of the description of the upper room into which the townspeople finally gain access. Here, the descriptive details of decay and rotting hit their climax. "Acrid pall of the tomb" is self-explanatory, but notice also how the color of the curtains is "faded," how the silver of the toiletry items is "tarnished," and how when some other items are picked up, they leave a "pale crescent in the dust."