The Confessions of St. Augustine ranks as one of the more important books in the history of religion and literature for both its content and its formal innovations.
In terms of form, it is the earliest example of spiritual autobiography in the western traditions, and was in many ways the seminal book in the genre. Many subsequenbt books, such as Rousseau's Confessions or Hogg's Confessions of a Justified Sinner follow an Augustinian pattern.
For historical information, Augustine provides us with unique insights into the daily life and culture of Roman Africa, as well as the social and economic contexts of Christianity and Manicheanism.
Augustine's work was also central to the formation of Roman Catholic theology. His approach to original sin is still accepted as Roman doctrine, as is his notion that the state of graced or lack thereof of the priest does not effect the efficacy of the sacraments (Donatist controversy). He also wrote among the more insightful works on predestination and free will.
The Confessions is a spiritual autobiography, covering the first 35 years of Augustine's life, with particular emphasis on Augustine's spiritual development and how he accepted Christianity. I very much enjoyed reading book 11 through 13 which discussed detailed interpretations of the first chapter of Genesis, which describes the creation of the world. I think it is important to study the history of religion and interpret it in your own way, applying it to other value system within your life. Religion can be interpreted in so many ways, and because of books like this we can apply morals and values to ourselves. In book 11 we learn about the first verse of Genesis, in which God begins the creation of the world; discussion of the nature of time and eternity. In book 12 we discuss the second verse of Genesis, with emphasis on the Word (Christ); discussion of how scripture may be interpreted, which was actually my favorite book to read because its interpretation analysis was very interesting, and easy to apply to our environment. In book 13 it explains the seven days of creation (the remainder of Genesis Chapter 1), which is also VERY interesting.