The works outline Augustine's sinful youth and his conversion to Christianity. It is widely seen as the first Western autobiography ever written, and was an influential model for Christian writers throughout the following 1000 years of the Middle Ages. It is not a complete autobiography, as it was written in his early 40s, and he lived long afterwards, producing another important work (City of God); it does, nonetheless, provide an unbroken record of his development of thought and is the most complete record of any single individual from the 4th and 5th centuries. It is a significant theological work. In the work St. Augustine writes about how much he regrets having led a sinful and immoral life.