In St. Augustine's Confessions, he explains that for a period of time he became a follower of the Manichean teaching. As explained by the New Advent Encyclopedia, Manichæism is a religion founded by the Persian Mani in the latter half of the third century. It purported to be the true synthesis of all the religious systems then known, and actually consisted of Zoroastrian Dualism, Babylonian folklore, Buddhist ethics, and some small and superficial, additions of Christian elements. As the theory of two eternal principles, good and evil, is predominant in this fusion of ideas and gives color to the whole, Manichæism is classified as a form of religious Dualism. While the religion has died out sometime after 1000 A.D., the religion is important because it was one of the many religions which competed with Christianity while Christianity was still growing. Certainly, it is in contrast with his early experience with Manicheanism that St. Augustine's understanding of Christian theolog