Why did origen and augustin oppose millennialism?
Most of the earliest Fathers either taught a literal millennium (though clearly differing on details) or were silent on the matter, Origen was the first to publically break with this tradition. Thomas D. Lea comments, “Before the time of Origen it was reasonably common to find the fathers expressing their belief in a personal second coming of Christ together with a millennial reign of the saints with Christ after their resurrection from the dead. Origen denounced millennialism perhaps because of his view that it overemphasized the sensual and the material. During the beginning stages of Christianity and at the time of the early Church fathers,variations on Platonism were the dominant mode of thinking.Augustine was a Neoplatonist who felt a necessity to mix Neoplatonism and Christology that results in a noteworthy tension between positive and negative theology: the desire to say something about God and the desire to respect His infinite alterity.
Plato’s, and also Origen’s, belief in the inherent immortality of the soul prevented them from accepting millennialism. As philosophers, they had an unrestrained approach to Biblical interpretation blurred the lines between Christian doctrine and Greek philosophy. So he fully accepted the “immortality of the soul” as did Plato, and could not accept Millennialism. He also did not want to think as a jew, commonly arguing with them, so he had to differ somewhat in his ideas. When he was young, the Roman emporor forbid anyone to change their religion. Origen’s father died standing for Christianity, so while all of the above stated reasons are acceptable, my personal opinion is his resentment of Christianity and his fathers death, and so he did not fully embrace biblical teachings, however he twisted them.