Augustine begins Book II with a candid confession of the deep and burning sexual desires that he experienced as a teenage boy. He "ran wild in the shadowy jungle of erotic adventures." He realizes, however, from the remove of middle age, that his one desire was simply to love and be loved. He says that as an adolescent he was misguided into thinking that concupiscence was the path to love. He says that the wrath of God was heavy on him then, but he didn't realize it. He explains that the dissatisfactions and troubles he endured in his adventures were punishments from God.
He also claims that if someone had put restraint on him and instructed him in the difference between love and lust, he might not have sinned so greatly or suffered so much. As evidence of his Neoplatonic background, Augustine positions the lustful drives of his adolescence as part of the desire for beauty, and how easily he - and all mankind - are deceived into thinking that this is the only way to obtain and understand beauty. He thinks that if he had been guided into a wise marriage, (although he doubts he could have confined sex to procreation) he might have learned these things earlier. In this book he also discusses the Manichaeism ideal of celibacy, and quotes scripture to that effect.
Augustine's mother Monica admonished him severely to not commit the sin of fornication, and, especially to not commit adultery with another man's wife. He considered this "womanish advice" and took no notice, but he sees now that these were God's warnings transmitted through his mother. He was not married off because his parents were ambitious, and it was important to make an advantageous marriage that would not have been possible at his young age. Augustine therefore had no checks on his sexual experimentation.
Augustine's friends appear to have been typical teenage boys, prone to rebellion and high spirits. He fell in with a group that not only encouraged his exploits, but also made him feel that he needed to invent wrongs that he hadn't committed in order to impress his friends. One night he and his friends robbed the fruit off a pear tree near Augustine's father's vineyard. They didn't eat the fruit themselves, but rather threw it to the pigs. Augustine examines this pointless act of theft and surmises that adolescents want to do evil things because they do not understand the nature of beauty or goodness.
Augustine asserts that all good and beautiful things on earth are only so because they are part of God. The things of the earth are the lowest on the scale of goodness and beauty; the further up the scale and the more spiritual things become, the nearer they are to God and the more beautiful and good they are. Sins are committed for love or out of the desire for beautiful or good things that are on the lowest end of the scale because that soul does not yet understand that the material things are only part of the beauty and goodness of God.
In the next passage, Augustine explores many of the virtues of his day: pride, ambition, soft endearments, curiosity, simplicity, the desire for a quiet life, abundance, generosity, and excellence are all exposed for the vain human desires that lie at their bottom. God is the fount of all virtue, and Augustine explains that any "virtue" that is not founded in obedience to God is an illusion, and possibly a sin.
Augustine goes on to explain that he didn't really want the pears (for he had access to better ones), but that he somehow wanted to feast on the wickedness of the theft. He calls on God to help him inquire into the nature of his pleasure in the theft. He admits that if he had been alone he would not have done it. There was no pleasure in the actual obtaining of the pears, nor did he eat them. "Friendship can be a dangerous enemy," he says, and goes on to explain that once the theft was proposed, he would have been ashamed to not go through with it.
Augustine ends Book II with an anguished plea: "Who can untie this extremely twisted and tangled knot?" He doesn't wish to inquire any further into the matter. The higher things, the things of God, are what he desires now. Justice and innocence are his goals, and he will no longer contemplate the sins of his youth.
When he was 15, Augustine came home from the nearby town of Mandauros, where he had been studying. His family brought him home so that they might gather enough money to afford to send him to Carthage to study. He was a promising and intelligent boy, and his family was willing to make sacrifices for his future. Though he, throughout Confessions, criticizes his secular education, it is plain that he honors his family for the effort they put into his education. Augustine admits that his parents were ambitious for him. Patrick was actually quite proud of himself: though only a middle-class farmer, he did more for Augustine than many richer men did for their sons. It is also evident that Augustine felt quite guilty for the misdeeds he committed during this time, because his family was working so hard for his advancement.
During this time Augustine was idle: he didn't have school or work or a wife to occupy his time. He, along with other adolescent boys, frequented the public baths and roamed the streets in the evenings. He probably wasn't quite as bad as his companions, for according to contemporary sources he was steady, sober, and well-respected, but he did fall in with some wild companions, and undoubtedly committed some of the sins he recounts.
This book mainly serves to explain the lustful desires (sexual and otherwise) for beauty that can lead humanity into error. He is not as understanding of these youthful urges as we might like him to be, and offers no explanation for why young men would be particularly driven to deeds such as sexual experimentation or vandalism. He had no knowledge of modern endocrinology, which explains the hormonal origin of much of the rebellious, sexual, and wild behavior of adolescents. From this perspective Augustine's comments may seem needlessly prudish, but all of his anecdotes serve as supports for his carefully constructed argument for the Neoplatonic ideas of the greater spiritual good of Godly rather than material things.
Augustine is continually seeking the "first principles," or the origin of all his desires, sins, follies, and thoughts. He tries to understand, in very deconstructed terms, the desires of human nature. He assumes (and again this is a Neo-Platonic rather than a strictly Christian point of view) that every human desire must have some origin that can be arrived at logically. Subsequent ages, including our own, have held that much of human behavior has no origin in logic or thought, but is rather the product of many different factors (including brain chemistry, hormones, uncontrollable social or economic factors, and even exterior chemical causes such as food denaturing or toxic contamination). Augustine holds tight to the idea that everything that human beings do has a reason, and, while he cannot always fathom it, even in himself, it is useful to delve as far into the logical origins of motivation as possible.
Again, Augustine comes back to the loveliness and completeness of God. Near the end of Book II, in a passage of particular balance and precision, Augustine carefully and persuasively breaks down many common virtues into the vain human desires that they actually are. By the end of Book II Augustine has made an excellent case for the totality and omnipresence of God, and the utter futility of searching for anything other than God.