St. Leo the Great

Leo was born around the year 400, of a Tuscan family, and rose through the Roman clergy as a deacon of weight and learning under Popes Celestine and Sixtus III. While he was away in Gaul on an imperial commission, the clergy and people of Rome elected him bishop of the city, and he was consecrated in September of 440.

His pontificate fell in the years when the Church was tearing itself apart over the person of Christ. The archimandrite Eutyches of Constantinople taught that after the union the Lord had but one nature, the human swallowed up by the divine. When Eutyches was condemned and then restored by the violent synod that met at Ephesus in 449, the synod the Church has ever after called the Robber Council, Flavian of Constantinople appealed to Rome.

Leo answered with his Letter to Flavian, the Tome, setting out in measured Latin the confession of one Christ in two natures, each nature keeping its own proper character and acting in communion with the other. Two years later, at the Council of Chalcedon in 451, the Tome was read to the assembled Fathers, and the acts record that they cried out, This is the faith of the Fathers, Peter has spoken thus through Leo. His letter became, with the council's own Definition, the dogmatic charter of the Fourth Ecumenical Council.

He was as much a shepherd of the city as a teacher of the Church. In 452, when Attila and the Huns marched on Rome, Leo went out to meet him and persuaded him to turn back. Three years later, when the Vandals under Gaiseric entered the city, Leo could not prevent the sack but won from them the lives of the people and the churches. His sermons, preached through the cycle of the Christian year, remain among the clearest voices of the early Latin Church.

He governed the Roman Church for twenty-one years and reposed on the tenth of November, 461. The Church keeps his memory on the eighteenth of February. He is one of only two bishops of Rome on whom both East and West have set the title of the Great.