Jacob's Book
Jacob's book is symbolic of his plagiarism, greed, and opportunism. When his student dies, Jacob opportunistically decides to appropriate his student's story idea and write a book from it (a book which the student said would be a guaranteed bestseller). For his own ends and because of his greed, Jacob steals something that doesn't belong to him, thereby creating the main conflict of the book.
Threatening emails
A reoccurring motif in the novel is the threatening emails that Jacob receives after he plagiarized the story idea from his student (who likely plagiarized his idea from someone else). As Jacob's popularity reaches a fevered pitch, he receives his first threatening email, and it goes from there. This motif ratches up the tension in the novel and creates the novel's main conflict.
Jacob's Vermont MFA Program
The MFA program Jacob teaches at in Vermont is symbolic of his career downfall. Jacob had previously written and published a modestly successful book, but he was unable to craft anything else. Because of that, he took a job teaching at a Vermont MFA program to make ends meet. Any writer who enjoyed tremendous success would not have to take such a job. After enjoying success initially, Jacob had neither success nor much of a career.
Jacob's student
Jacob's student is symbolic of youthful arrogance and pride. Jacob heard his student boast about a plot for a novel that he came up with that would be an overnight, guaranteed bestseller. Realizing that his student had likely never written a word, Jacob was skeptical of his student and his pride in his idea.
The moral pitfalls of plagiarism
The novel is an allegory for the moral pitfalls of plagiarism. In the novel, Jacob thinks that he was safe to plagiarize his student's idea because he was dead. He very quickly discovers that isn't true: Jacob's student plagiarized his idea from someone else, putting Jacob in a bad position.