Final answer:
Pelagianism is a theological belief that denies the necessity of sacraments for salvation and views humans as exceptionally good. However, this belief was condemned as a heresy by St. Augustine, who argued that divine grace is necessary for salvation due to the effects of original sin.
Step-by-step explanation:
Pelagianism is a theological belief that views human nature as exceptionally good and denies the necessity of any sacraments for salvation. It holds that humans can achieve salvation through their own efforts without the need for divine grace. This belief was condemned as a heresy by St. Augustine and countered by the doctrine of original sin, which teaches that humans are inherently sinful and in need of redemption.
Augustine argued that humans cannot achieve salvation on their own and that divine grace is necessary. He believed that God's grace is needed to overcome the effects of original sin and to bring about true moral and spiritual transformation. Augustine's views on salvation and grace influenced later Christian theology, including the teachings of Martin Luther and John Calvin.