How does Augustine (in Confessions) establish his authority as a writer? What does he do to compel us to read and listen to him?

Aurelius Augustinus, commonly known as St. Augustine, was a fourth-century teacher of rhetoric, philosopher, and Christian theologian of Roman African decent. He was born and died in Algeria but spent the majority of his life in the Roman Empire. As his wise writings were thought to be the second most important writings after the Bible, Augustine was ordained and consecrated bishop of the city of Hippo and is considered one of the most influential Christian theologians, writers, and Church Fathers in world history.
Augustine wrote several books and texts which greatly influenced almost the entirety of Western philosophy and theology, metaphysics, ethics, and even politics. However, his most important writings of all time are his Confessions, the Christian book The City of God, and the theological text Of Christian Doctrine.
The Confessions of Saint Augustine (original title: Confessions in Thirteen Books) is essentially Augustine’s autobiography, and it is even considered the first autobiography ever written in Western philosophy and literature. The text is compiled of thirteen books written in Latin, in which Augustine writes about his wild and sacrilegious past and his later conversion to Christianity.
Unlike most autobiographies, The Confessions of Saint Augustine doesn’t follow a specific narrative; instead, the book seems to be written in the form of a chronological, retrospective memoir in which Augustine analyzes his life as he remembers it. Because of his masterful storytelling, his aphoristic language, and his wise and memorable quotes, Augustine managed to establish his authority as a notable and important author of Christian theology and Western philosophy.
Augustine may have influenced a lot of writers and philosophers; however, I must mention that he himself was influenced by many Ancient Greek theorists and philosophers, and the majority of his work is based on Plato’s philosophy. In fact, his most important writings, in which he discusses various subjects such as time, free will, the existence of God, faith, morality, and human nature, are infused with heavy Neoplatonism.
Augustine is among the most important Christian writers who believed that God does not have a shape, form, or body but rather exists as an infinite, ethereal, and incorporeal entity that influences everything and everyone in the universe. One of the main reasons why Augustine presents such attractive reading material is the fact that he was bold enough to combine analytical thinking and logic with religion and faith. Thus, in addition to being a prominent Christian figure, St. Augustine greatly contributed to the agnostic philosophy and community.
https://www.ling.upenn.edu/courses/hum100/augustinconf.pdf