(c.150 - c. 215) Presbyter of the church in Alexandria, Clement has been recognized as one of Christianity's greatest scholars. He was versed in the Old and New Testaments, apocryphal and gnostic writings, Greek literature, and philosophy. Clement succeeded Pantaenus as head of the catechetical school at Alexandria, where he taught, among others, Origen and Alexander of Jerusalem. The oldest known Christian hymn was written by him, "Shepherd of Tender Youth."