c. 185 – 254

Origen of Alexandria: school, On First Principles, the Hexapla, Against Celsus

Origen was the son of the martyr Leonides, who died under Septimius Severus. At 18 Bishop Demetrius appointed him to prepare catechumens, and he then headed the philosophical school of Alexandria. Later he came into conflict with Demetrius, one reason being Origen's ordination by Palestinian bishops without the consent of his own bishop. In the 230s he moved to Caesarea in Palestine and taught there for another twenty years with the support of the wealthy Ambrose.

Among his works are On First Principles, the first attempt in Christian history at systematic theology; the Hexapla, which set six versions of the Old Testament in parallel columns; and Against Celsus, the most substantial reply to pagan criticism of Christianity. Even in his lifetime his views provoked controversy (Methodius of Olympus), and later they were partly condemned as heresy.

During the Decian persecution in 250 Origen was tortured and soon died of his wounds in Tyre.