Of Anthony the Monk
What sort of a man the monk Anthony was, who lived in the same age, in the Egyptian desert, and how he openly contended with devils, clearly detecting their devices and wily modes of warfare, and how he performed many miracles, it would be superfluous for us to say; for Athanasius, bishop of Alexandria, has anticipated us, having devoted an entire book to his biography. Of such good men there was a large number at one time during the years of the Emperor Constantine.
Source: Ecclesiastical History (New Advent)