Final answer:
Augustine's mother, Monica, passed away during their return to North Africa after his conversion. Augustine's role in free will philosophy and his impact on the Donatist controversy are significant aspects of his influence, with divine grace being central to his arguments on human choice and morality.
Step-by-step explanation:
The text hints at events happening to Augustine on his journey back home, but the snippets do not specify any incident involving Augustine and Monica together during a return home.
However, in the historical context, Augustine's mother, Monica, was a devout Christian who had significant influence on Augustine's spiritual development. On the way back to their homeland of North Africa after Augustine's conversion, Monica fell ill and passed away at the port city of Ostia in 387 AD.
This event is well documented in Augustine's confessions, which describe his grief and contemplation of life and death following his mother's sudden departure.
Augustine's ideas about free will continue to be a point of discussion regarding their compatibility with divine omniscience and predetermination. Augustine contested the deterministic viewpoints such as those of the Manicheans and argued that humans have the capability to choose the good.
He saw human existence as a battle between two wills: the will toward goodness and the will toward sin. Augustine believed that divine grace is necessary for selecting the right path, though we have the freedom to make our own choices between sin and virtue.
Augustine's influence also extended to resolving the Donatist controversy in North Africa. As the bishop of Hippo, Augustine fiercely opposed the Donatists and was instrumental in their expulsion from the church at the 411 Council of Carthage, which dealt a significant blow to this sect.