He was bishop of Heraclea in Egypt. Saint Athanasius says he was doubly a martyr, under the heathens and under the Arians. When Maximinus Daia, or Daza, persecuted the Christians in 310, he gloriously confessed the faith, for which one of his eyes was bored out, and probably the sinews of one ham were cut, as in the case of Saint Paphnutius and others. The marks of his sufferings rendered him conspicuous in the council of Nice in 325, in which he exerted his zeal against the Arians. He accompanied and defended Saint Athanasius in the council of Tyre in 335, as was related in the life of that saint on the 2nd of May. When the tyrant Gregory had usurped the patriarchal chair of Saint Athanasius, he, with Philagrius, prefect of Egypt, an apostate to Arianism under Constantius, travelled over all Egypt, tormenting and banishing the Catholics; and Saint Potamon, for his distinguished zeal, was by their order beaten on his back with clubs so long as to be left for dead. However, by the help of medicines, he came to himself, but died shortly after a martyr for the divinity of the Son of God in 341, as Saint Athanasius relates.