How we cite our quotes: (Chapter.Paragraph)
Quote #4
His life had always been one of sweet evenness… and one of the things that disturbed it was the miserable ends some of his students came to. (7.121)
Matt is thinking about how much he dislikes his students dying. The whole Lot practically is composed of his students, though, which explains why he (more than anyone else) is especially upset by what happens to the Lot. It also explains maybe why he dies when the Lot does: he's wrapped up in the life of the place, so the town's death is his death, too.
Quote #5
"I will see you sleep like the dead, teacher." (9.238)
Mike Ryerson is threatening Matt. But the threat is odd: is he telling Matt he will die? Or that he'll sleep like vampires sleep, which is like the dead? Maybe even the vampires aren't sure whether they're dead or not.
Quote #6
No one pronounced Jerusalem's Lot dead on the morning of October 6; no one knew it was. Like the bodies of previous days, it retained every semblance of life. (14.6)
The fascination with the idea that you can't tell dead from life seems to be applicable to small towns in general, not just ones infested with vampires. Small towns staying the same, never going anywhere, home to corruption and evil—are they all just "dead" in the first place? Parkins Gilman thought so.