What you say of me does not come from yourselves;
it is the Spirit of my Father speaking in you.

Pope Sylvester and Constantine

We end the calendar year with the feast of Saint Sylvester I, who in God’s providence was elected Bishop of Rome just after Constantine issued the Edict of Milan.  With Christianity thus legalized throughout the Roman Empire, Sylvester was charged with bringing the Church out from the catacombs and into the public square.  His efforts at preserving and purifying the faith, as well as developing the Church into a cultural and political force, bore much fruit.  Within 75 years, Christianity became the official state religion of the empire.

From Defending the Faith:

Sylvester was a Roman, the son of Rufinus. He was ordained a priest by Marcellinus. Chosen Pope in 314, he continued the work of organizing the peacetime Church so well begun by St. Miltiades. Sylvester saw the building of famous churches, notably the Basilica of St. Peter and the Basilica of St. John Lateran, built near the former imperial palace of that name. It is quite probable too that the first martyrology or list of Roman martyrs was drawn up in his reign.

Towering over all other events of his pontificate, however, was the first ecumenical or general council of the Church. An ecumenical council represents the entire teaching Church as opposed to a diocesan synod or a metropolitan or a national council. The ecumenical council, like the pope, is infallible in matters of faith and morals because it is the voice of the teaching Church.

A heresy had arisen in Alexandria and at that time was making great headway throughout the East, the heresy of Arius, a priest of Alexandria. Arius taught that Jesus Christ was not truly divine, that His nature was not the same as that of the Father but only similar. It was to study this question and to pronounce the true teaching of the Church that bishops from all parts of the empire made their way to Nicaea in 325. The Emperor Constantine, still a catechumen, had at first made light of the matter, but when his eyes were opened to the danger of Arian doctrine by Hosius of Cordova, he became so interested that he went to Nicaea himself.

Pope Sylvester sent two legates to represent him Vitus and Vincentius, and it seems that it was the Pope who suggested the term consubstantial to describe the relation of Christ’s nature to the Father. The Council condemned Arius and drew up the famous Nicene Creed. This creed, said in all the Catholic Churches throughout the world, proclaims that Jesus is true God of true God consubstantial with the Father.

St. Sylvester died in 335. He was buried in a church which he himself had built over the Catacomb of Priscilla on the Via Salaria. His feast is kept on December 31.

Lord,
help and sustain your people
by the prayers of Pope Sylvester.
Guide us always in this present life
and bring us to the joy that never ends.

We ask this through our Lord Jesus Christ, your Son,
who lives and reigns with you and the Holy Spirit,
one God, forever and ever. Amen.