An epigraph is a creative and unique way to set the tone or theme for a book or novel. Often, an epigraph can be a quote, scripture, passage, or short blurb that serves as a small introduction to the book you are reading. Though some epigraphs seem irrelevant or confusing, they are important. It is a smart idea to find out more about the epigraph (e.g., its source, age, and author) in order to read the story you are about to journey on with more accuracy and mindfulness. Epigraphs are considered literary devices and should be viewed as such.
A good epigraph will shape the book. At the end of the book, you should be able to look at the epigraph and understand its relevance clearly. For example, in Atwood's novel, the epigraph is by female Victorian novelist George Eliot and reads, "Every woman is supposed to have the same sets of motives, or else to be a monster." This sets the themes of gender roles, fear, and shame. These can all be seen throughout the novel through Gilead's male leadership, especially in the public execution of those who contradict the gender roles (i.e., Gilead's laws). If you do not conform to what you are supposed to be, you will be seen as a monster. The epigraph shows how relevant and long-lasting this notion is and has been.