St. John Chrysostom (ca. 347-407) was a famous and controversial fourth century bishop. He studied law as a young man, but then went off to the mountains for some years and lived an ascetic life; after this he became a priest and served in his native city of Antioch. It was there that his powerful and eloquent preaching earned him the nickname "Chrysostom" (golden-mouthed).
In 398 John was elected bishop of Constantinople, the imperial capital. John tried to ignore politics as he exercised his ministry, but he was often caught up in controversy and intrigue. His sermons, often critical of the rich and powerful, made him many enemies, and his simple lifestyle and efforts at reform (such as deposing bishops who were mere political appointees) further alienated the ruling class.
In 403 John’s enemies, led by the empress and the bishop of Alexandria, charged him with heresy and misdeeds. The emperor sent him into temporary exile, but soon recalled him; in 404, however, John was exiled permanently, first to Armenia, then to Spain, where he died in 407 after several years of suffering and physical exhaustion.
St. John’s homilies were noted for their great scholarship and for being very practical and straightforward. He is considered a Doctor (an eminent and reliable teacher) of the Church.