Mark of Ephesus (Greek: Μάρκος ό Εφέσιος, born Manuel Eugenikos) was a hesychast theologian of the late Palaiologan period of the Byzantine Empire who became famous for his rejection of the Council of Ferrara-Florence (1438–1439). As a monk in Constantinople, Mark was a prolific hymnographer and a devoted Palamite. As a theologian and a scholar, he was instrumental in the preparations for the Council of Ferrara-Florence, and as Metropolitan of Ephesus and delegate for the Patriarch of Alexandria, he was one of the most important voices at the synod. After renouncing the council as a lost cause, Mark became the leader of the Orthodox opposition to the Union of Florence, thus sealing his reputation as a defender of Eastern Orthodoxy and pillar of the Eastern Orthodox Church. Early life Mark was born Manuel in 1392 in Constantinople to George, sakellarios of Hagia Sophia, an Orthodox deacon, and Maria, the daughter of a devout doctor named Luke. Mark learned how to read and write from his father, who died while Mark and his younger brother John Eugenikos were still children. Maria had Mark continue his education under John Chortasmenos, who later became Metropolitan Ignatius of Selymbria, and a mathematician and philosopher by the name of Gemistus Pletho. Activity at the Council of Florence and aftermath Mark was the only Eastern bishop who refused to sign the agreement with the Roman Catholic Church on a compromise formula, "ex filio", for the Filioque clause disagreement during the Council of Ferrara. He held that Rome continued in both heresy and schism. Likewise the Catholic church considered him to be a heretic. He also rejected the doctrine of Purgatory, in that he objected to the existence of a purgatorial fire that "purified" the souls of the faithful. Death He died peacefully at the age of 52 on June 23, 1444, after an excruciating two-week battle with intestinal illness. On his death bed, Mark implored Georgios Scholarios, his former pupil, who later became Patriarch Gennadius of Constantinople, to be careful of involvement with Western Christendom and to defend Orthodoxy. According to his brother John, his last words were "Jesus Christ, Son of the Living God, into Thy hands I commit my spirit." Mark was buried in the Mangana Monastery in Constantinople. Posthumous miracle and canonization The Eugenikos family celebrated each anniversary of Mark's death with a eulogy consisting of a service (akolouthia) and synaxarion of a