They used to hang men at Four Turnings in the old days. Not anymore, though.
-- Philip (1 and 26)

Importance: These are both the first and last sentences of the book. Philip says them as the narrator in both instances. The author uses them to introduce the story and create an air of mystery concerning why Philip would begin this way. She closes the books with the same lines indicating that Philip knows he is responsible for Rachel’s death, but also that the only punishment he will receive will be of his own making.

Hitherto, when I had thought of my cousin Rachel—which I did but sparingly, brushing her name from my mind as one does all things unpleasant—I had pictured to myself a woman resembling Mrs. Pascoe, only more so.
-- Philip (chapter 3)

Importance: Prior to meeting Rachel, Philip tries to picture what she looks like. In his mind, Rachel takes on all the worst...