Gregory of Nazianzus

Gregory of Nazianzus was born around 329, a classically trained orator and philosopher who would infuse Hellenism into the early Church and set the template for Byzantine theological style. Alongside Basil of Caesarea and Gregory of Nyssa - the trio known as the Cappadocian Fathers - he refined Trinitarian doctrine at a hinge moment when Greek and Latin theologians were hammering out how three Persons relate within one God. He served briefly as Archbishop of Constantinople from 380 to 381, but his lasting mark was rhetorical: the patristic age's most accomplished stylist, writing theology that still shapes modern thought on the Trinity. Venerated as a saint in both East and West, he is counted among the Doctors of the Church and the Three Holy Hierarchs, and briefly claimed as patron of medieval Bosnia's Kotromanić dynasty in the 15th century. He died on 25 January 390.