How we cite our quotes: (Part.Chapter.Paragraph)
Quote #1
"That was pretty good, eh?" said Idabel. "I'll bet you thought the devil was hot on your trail."
Florabel said: "Not the devil, sister…he's inside you." (1.1.138-39)
The twin sisters, Idabel and Florabel, talk about the devil as though they knew him personally. Their casual chatter indicates that the presence of the devil is part of everyday life for them. Florabel's accusation, that the devil is inside of Idabel, could mean a couple of things: one, that Idabel is truly, ultimately evil in her sister's eyes or, two, that talk about the devil isn't all that serious.
Quote #2
Sometime later a thought of them echoed, receded, left him suspecting they were perhaps what he'd first imagined: apparitions. (1.1.152)
When Florabel and Idabel disappear into the night, Joel could almost fool himself into thinking that they had never been there. Comparing the girls to apparitions (a fancy word for ghosts) creates a sense of eeriness that's very common in the Southern Gothic genre, and also alerts the reader (that would be you, Shmooper) that things might not all be as they seem.
Quote #3
But Joel, scowling at a dream demon, was unaware when the woman bent so intently towards him and peered into his face by the lamp's smoky light. (1.1.154)
While the devil, in Florabel and Idabel's banter, is not so scary, the "dream demon" that haunts Joel's sleep seems much more sinister. We know at this point that Joel's mother has recently died, so it wouldn't be surprising if he were suffering from nightmares. This tiny little turn of phrase clues us in to Joel's dark inner life.