10th November - Leon was born towards the end of the 4th century, some say he was born in Tuscany, some say in Rome. Other documents say it was in Etruria. His father's name was Quintianus and the story of his childhood is not well known but his first known history dates back to 418. He was then an acolyte to Pope Zosimus.
He had a deep knowledge of the Church and was very attractive to the crowd with his words and gestures. Pope Celestine I ordained him a deacon and appointed him archdeacon in 432. As Pope Sixtus III's right-hand man and trusted man, Leo was a great help to him in opposing the pelagians. He was sent by this pope to arbitrate a conflict in Gaul, at the request of the palace of Ravenna, between General Aetius, then Patriarch, and the Prefect of the Praetorium Albinius. His fame spread throughout the city. Pope Sixtus III died while carrying out this mission. He was immediately elected Pope by the people of Rome and was expressly recalled to Rome, where he was installed as Peter's successor on 29th September 440.
Although reserved and discreet, Pope Leo I was serious and prudent, a man of knowledge and discipline. His closest advisers were Saints Peter Chrysologus and Posper of Aquitaine. Both society and the Church lived in turbulent times during his pontificate. In society, for example, he turned Attila back in 452. In 455, Genséric's looting could not be resisted, but he managed to negotiate that the town would not be burnt and that the inhabitants would be spared. In ecclesiastical life, he led three zones, the city of Rome and Italy, opposing the Manichean sects and Pelagianism. In 443, he brought together many bishops and priests to be vigilant against the sects. He forced the bishops to attend the annual synod of Rome, and at the same time reminded them of the conditions for being a pastor. In Gaul, Spain and North Africa, he encouraged the people in the fight against Priscillianism and invited the bishops of Astorga to convene a Council to counter this heresy. In the Eastern world, he appointed the Bishop of Thessaloniki to assist him.
On the doctrine of faith, there was much debate about Christ, especially among Byzantine theologians. In his work "Tome to Flavian", published on 13 June 469, Leo I teaches that Christ is both God and man. Theodosius II convened the Council of Ephesus in 449, but Eutychus prevented the Pope's representatives from speaking. Shortly after the death of Theodosius II, the Empress of Pulcheria convened a new council in Chalcedon in 451. The audience was convinced that "Peter speaks through the mouth of Leo". It should be noted that he was the forty-third pope, and the first to bear the name of the reign of Leo. He is also the first successor of Peter to have had the title of "Doctor of the Church". He died on November 10, 461, and was the first pope to be buried in St. Peter's Basilica in Rome. His letters concerning the life of the Church and the Holy See number one hundred and seventy-three. All his sermons, ninety-seven in number, from the great feasts during his pontificate are preserved.
