Final answer:
Augustine of Hippo converted to Christianity after being inspired by Antony of the Desert and played a crucial role in resolving the Donatist controversy and shaping Christian doctrine on issues like grace and free will.
Step-by-step explanation:
Augustine of Hippo, an influential Christian philosopher and theologian, was inspired to convert to Christianity after reading about Antony of the Desert, the Egyptian hermit. His conversion was immediate, signifying a pivotal moment in his journey of faith. Augustine became a pivotal figure in the Church, effectively ending the Donatist controversy and defending theological orthodoxy against various heresies, including Pelagianism and Manichaeism. His works like The City of God are essential in Christian literature, addressing issues such as the nature of God's kingdom and the distinction between the heavenly and the earthly realms.
Augustine's conversion and subsequent efforts were vital in shaping medieval philosophy and Christianity's development. His teachings on free will and divine grace emphasized human ability to choose the good while recognizing the need for divine assistance. Despite his original sin beliefs, he maintained that it was within our power to turn towards God's grace and choose goodness over sin. Augustine's intellectual confrontation with the Donatists at the Council of Carthage led to their expulsion from the Church and significantly reduced the presence of the sect in North Africa.