This is the final Book of the autobiographical part of the Confessions (the concluding four Books address more strictly philosophical and theological issues). Book IX recounts some of the events directly following Augustine's conversion: his retirement from his secular post, his baptism with Alypius and Adeodatus, a shared vision with Monica at Ostia just before her death, and a section of praise for her.
[IX.1-15] With the complete emergence of Augustine's free will in fully embracing God, he knew he had to retire from his position as a teacher (a salesman of loquacity). Not wishing to cause a stir, he waited until the next period of vacation before leaving his post--at this point, recurrent chest pain would have excused his withdrawal in any case. Meanwhile, Nebridius and another friend, Verecundus, had also decided to follow Augustine in converting to Catholicism.
Having shed his worldly occupation, Augustine continued to read and write. His chief works during this period were dialogues that set out the Neoplatonist reading of Christianity he had come to embrace. These he now sees as prideful works, though he does not retract anything specific from them. Augustine also had a powerful experience reading the Psalms at this point: "emotions exuded from my eyes and my voice."
There is a brief glance back to the Manicheans here, for whom Augustine now had nothing but pity and a lingering disgust. Now that he had saved himself, he began to wonder what to do about people who were as lost as they were.
Augustine was finally baptized, by Ambrose and in the company of his son Adeodatus and his friend Alypius. He immediately began to take greater part in Ambrose's congregation, participating in a sit--in against the anti- Catholic policies of Arian Justina (the mother of Valentinian II).
[IX.16-37] After recounting these events, Augustine turns his attention to Monica. Recalling her devout, humble, and wise nature over the course of her life, Augustine praises his mother for maintaining peace with his father and among her friends. He also suggests that God was using her for a higher purpose--in part, to see Augustine safely into the arms of the church. Although his father Patrick has passed away, Augustine tells us that Monica finally persuaded Patrick to be baptized shortly before his death.
Part of the occasion for this reminiscence is a vision Augustine and Monica shared in Ostia after his conversion and just before she fell ill and passed away. Augustine tells this story next. Looking out over a garden in Ostia, Augustine and Monica were discussing the nature of the reward met by saints in the afterlife. In the attempt to conceive of this paradise, Augustine recalls, they sought past earthly bodies to the stars, then went further, seeking for the answer inwardly (in the nature of their own minds).
Still chasing this idea through dialogue, mother and son reach a kind of eternal wisdom (again a transient experience): "we touched it to some small degree by a moment of total concentration of the heart." Unlike Augustine's previously recounted visionary ascent (after first reading the Neoplatonists), this one seems to be a quest for truth infused by love; the shared nature of the experience is in part a testimony to this change.
Attempting to describe the experience further, Augustine postulates that, if everything (including the soul) were utterly quiescent and unmoving, God would speak through himself rather than through any mediation. This is similar to what he and Monica experienced. "Eternal life," he writes, "is of the quality of that moment of understanding."
Following the vision, Monica told Augustine that she felt she had done all she had to do on earth. She fell gravely ill soon thereafter. Exhibiting an indifference as to whether she was to be buried back in Thagaste or not, she told Augustine that "nothing is distant from God."
Augustine decided not to grieve over her death (since she was going to be with God), but he recalls feeling a great deal of pain nonetheless. Unable to answer rationally why he was so sad, Augustine concludes nonetheless that weeping before God is acceptable because God is infinitely compassionate. He closes the Book (and the story of his life) with a prayer for Monica's soul.