Note 610 — PHOTIUS BIBLIOTHECA OR MYRIOBIBLON⁠[6] (continued 5)

Flourished during the third century. He was a pupil of Irenaeus and an active opponent of the Gnostics. He was a presbyter of Rome, and became anti-bishop in opposition to Calixtus (Callistus), an adherent of Monarchianism (denial of the doctrine of the Trinity). The treatise Against Heresies was first discovered in a convent on Mount Athos in 1842.