St. John Chrysostom

St. John Chrysostom lived in the mid-4th century and died in 407. He was born in Antioch in what is now Turkey and after his conversion to Christianity became one of the major church fathers as well as a renowned theologian and preacher. He developed a liturgy which many Orthodox, and even some Catholic churches, follow today. He also wrote a variety of hymns and homilies which also survive. Here is an icon of him from the Hagia Sophia church in Constantinople:

Since he was such a scholarly-type, I went with a scholarly outfit for the day - bun and all: