A Commemoration Without a Vita
Phorbinus belongs to the large body of early Egyptian ascetics whose names the Church has preserved in its calendar even where no biographical narrative survives. He is listed only as part of a grouped commemoration alongside Theonas and Symeon, and the standard Orthodox reference sources supply no account of his birth, monastic formation, ascetic labors, repose, or relics.
By the dating given in those sources he is assigned to the 4th century, the era in which Egyptian monasticism reached its first great flowering in the deserts of Nitria, Scetis, and the Thebaid. While no source connects Phorbinus to a particular monastery, teacher, or recorded event, his memory is honored as one of the many desert fathers of that age whose lives were known to their contemporaries but not written down.