The first heretics among Christian thinkers were influenced by Neo-Platonism. Generally, they took on Gnostic beliefs that state the test of Christian truth is not the official teaching of the Church or the doctrine of the gospels, but a secret gnosis, a doctrine that is given by Christ to the chosen few. This body of doctrine was essentially a modified Neo-Platonism. Its main point was the idea that evil not a creation of God but the work of the devil. The problem of evil began to fill a large part of philosophical systems of orthodox Christian thinkers all the way to St. Augustine. Other issues also got a lot of attention, such as the question of the origin of the universe. Along with the theological debates about the mysteries of the Trinity and the Incarnation, came debates about the meaning of nature, substance, and person. From these discussions came Christian Neo-Platonism of the Alexandrian School that included Clement and Origen, and the later ideas of Christian Platonism described by St. Augustine. The philosophy of St. Augustine exemplifies he most important effort of the Christian mind during the patristic Era. It is a philosophy that is based around problems and their relationship to God and the aspects and destiny of the human soul.
The main points of his philosophy were associated with the existence of evil, and how evil could exist in a world that is created by God. He rejects the Manichean theory that evil has an origin apart from God and states that from the nature of evil it does not demand a direct act on the part of God, but only an act of God allowing evil.