Scythianus was a supposed Alexandrian religious teacher who visited India around 50 AD. He is mentioned by several Christian writers and anti-Manichaean polemicists of the 3rd and 4th centuries CE, including Cyril of Jerusalem, Hippolytus and Epiphanius, and is first mentioned in the fourth-century work, Acta Archelai, a critical biography of Mani from an orthodox perspective. Scythianus is thought to have lived near the border between Palestine and Arabia, and to have been active in trade between the Red Sea ports and India.
Hippolytus considered Scythianus as a predecessor of Mani, and wrote that he brought, before Mani, "the doctrine of the Two Principles" from India. According to Epiphanius, he was apparently trying to propagate the view "that there is something beyond the one who exists and that, so to speak, the activity of all things comes from two roots or two principles".
Epiphanius further explained that Scythianus wrote four books: Mysteries, Treasure, Summaries , and a Gospel (the "Gospel of Scythianus", also mentioned by Cyril of Jerusalem). Scythianus is said to have been to Jerusalem, where he disputed his doctrines with the Apostles.
The account of Cyril of Jerusalem states that after Scythianus' death, his pupil Terebinthus went to Palestine and Judaea ("becoming known and condemned in Judaea") and Babylon. He used the name 'Buddas', which could mean he presented himself as a Buddha and may suggest a link between his philosophy and Buddhism. Terebinthus brought with him the books of Scythianus, which he presented upon his death to his lodger, a widow with a slave named Cubricus, who later changed his name to Mani (from "Manes" in Persian, meaning "discourse"). Mani is said to have studied the books, which thereby become the source of Manichean doctrine.