The ORIGINAL Pope Leo
Have you been wondering these last couple weeks who the first "Pope Leo" was? Here's the tale of Pope St. Leo the Great.
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440 A.D.
Our pope this week came to power at one of Catholicism’s first major turning points – the collapse of the Roman Empire and the simultaneous rise of the Church as the caretaker of civilization. Spiritual and corporeal danger alike were brewing beyond the walls of the Eternal City, but this GREAT pontiff was up to the task.
The man we now know as St. Leo the Great was born in the Italian region of Tuscany, likely somewhere in the late 300s. Little is known about his early life, but we see him come on the historical scene around the year 430, when Pope St. Celestine I named Leo a deacon. For two years Leo served in Rome, but starting in 432 he was sent by the Roman Emperor to Gaul - modern-day France - to settle disputes between the military and civil leaders there. As it turned out, Leo was a naturally gifted diplomat – a trait that would serve him especially well later in life.
Sometime during his diaconate, Leo commissioned a book by another soon-to-be saint – the monk and theologian John Cassian – to condemn the heresy of Nestorianism, which taught that Christ wasn’t one united person, and also refused to call Mary the “Mother of God” – or Theotokos in the Greek, literally meaning “God bearer”. Instead, the Nestorians used the term “Christotokos” – Christ-bearer – and claimed that it was only Christ’s human nature that died on the Cross, not the divine person of Jesus. Turns out Leo was just warming up his heresy blasters, though. We’ll get to that in a bit.
By the year 440, not only had Pope Sixtus III died (being venerated as a saint soon afterward), but the Roman Empire was in steep decline. Barbarian invasions were on the rise, and the Church was in dire need of a pope with spiritual chops AND political savvy.
Thankfully, the Holy Spirit had just the guy.
Leo was consecrated pope on September 29, 440 to succeed St. Sixtus III. Leo was a very holy man, but as mentioned, was also extremely talented diplomatically when it came to politicking and governing.
In fact, because of the civil unrest and the declining influence of emperors in the West at that time, not to mention the natural stability that came with over two decades of one man leading the Church, Leo was one of the first popes in history who ended up playing the dual role of spiritual and temporal leader.
He was almost constantly dealing with the ambitions of emperors from East and West, and playing mediator when things got especially rough. One rather famous instance was Leo’s meeting with Attila the Hun – yes, THE Attila the Hun – in 452. Attila and his army were preparing to sack the city of Rome, but it was none other than our saintly pope who persuaded the barbarian king to turn around and leave.
No one really knows what was said in the actual meeting itself, but what’s known for certain is that a) it did indeed happen, and b) that it was Leo – not the other two civil leaders who accompanied him – who ultimately persuaded Attila to retreat. Beyond that are different accounts – there was a tale that Leo offered Attila gold, or that Attila was so impressed with Leo’s presence that he reconsidered, but my personal favorite came from the writer Paul the Deacon in the 8th century. Paul’s story claimed that during the meeting, a enormously giant man appeared, visible only to Attila, wearing priestly vestments and holding a giant sword. After seeing what appeared to be the gargantuan figure of St. Peter or Jesus himself, Attila apparently took off, and he may or may not have wet himself.
In all seriousness, one of my greatest surprises when visiting Rome for the first time last year was seeing this exact scene immortalized in the TWENTY FIVE FOOT TALL marble relief that adorns St. Leo the Great’s tomb. In the mid 1600s, Pope Innocent X – who some may remember as the likeness used for the devil in the famous painting of St. Michael the Archangel – commissioned artist Alessandro Algardi to sculpt the famous event, showing Leo and Attila meeting, and the latter reacting in horror at both St. Peter and St. Paul flying out of the clouds with swords drawn.
And people say Catholicism is boring.

As far as Leo’s greatest achievement – easily his most lasting one – was his defense of heresy on all sides, which culminated in him defining the dogma of the two natures of Christ at the Council of Chalcedon in 451.
Pretty much immediately after getting elected, Leo’s sole priority was keeping the Church whole. The Pelagian heresy – which taught that you could supposedly earn your way to heaven, instead of it being a free gift from God – was still rumbling in the Italian city of Aquileia. It’s worth mentioning that this is still an accusation leveled at Catholics even today by some non-Catholics, who falsely believe Catholicism teaches one must work their way into God’s good graces. Pun intended.
Leo also battled Manichaeism – a form of the Gnostic heresy which taught that the body and soul aren’t unified. It was more or less a Star-Wars-esque belief that there were good and evil forces in the universe still in a cosmic struggle, and generally that matter was bad, while the spiritual was good. For those keeping track at home, the correct teaching, of course, is that both body and soul are, to quote Genesis, “very good.”
In any case, Leo had no time for that nonsense. He insisted that the faithful point out the heretics, then demanded from said heretics repentance and a profession of faith, or otherwise face their own moral consequences. Leo even preached strongly to Christians to guard themselves against heresy at all costs. Understandably, at a time when all of civil society was crumbling around the Church, Leo’s duty as universal pastor compelled him to keep his flock safe at all costs.
When it came to the reason the Council of Chalcedon occured, at that time the Church was still working out all the technical details of Christ being both the divine Son of God while and also fully human. As a result, during Leo’s time what’s called the Monophysite heresy was in full force. This heresy taught that Christ only had one nature – “mono” meaning one and “physio” meaning nature – and denied that Christ bore a human nature completely like ours. Instead they taught basically that Christ the divine person was merely occupying a human shell, but wasn’t fully human.
The correct belief, of course, is that Christ had two natures – human and divine – contained within his one divine person. After all, if Christ didn’t have a fully human nature, he couldn’t be like us in all things but sin (as we learn in the Letter to the Hebrews), and if he didn’t have a fully divine nature he couldn’t actually be God.
Of course, Leo knew this, and fought hard toward the middle of his papacy to squash the growing heresy. This ultimately led to the Council of Chalcedon, the fourth ecumenical council of the Church, where Leo could set down once and for all the true dogma of Christ’s dual natures.
At the council, the so-called Tome to Flavian or Tome of Leo was read aloud to settle the matter once and for all. The account of the council reports that after it was read, the bishops cried out, “Peter has spoken through Leo. So taught the Apostles.”
Leo reigned as pope for 21 years, from 440 to 461. Not much is known about his death, other than he expired on November 10 – now celebrated as his feast day in the Western Church – and that he requested to be buried as close as possible to the tomb of St. Peter. His remains still reside in St. Peter’s Basilica, in an alcove to the left of the high altar.
As for his legacy, his reputation almost needs no introduction. Leo the Great was the first of now FOURTEEN popes to bear the name Leo – the most recent of which, we now all ought to know, is currently sitting in the Chair of St. Peter.
Five of those Popes Leo, including, of course St. Leo the Great, are now recognized as saints – the others being, Leo II, Leo III, Leo IV, and Leo IX.
Leo is also one of four popes to have the unique title of “The Great” be added after his name. This isn’t something official, necessarily, but rather something that’s given by popular acclaim because a pope’s especially great renown among the Christian people who knew him – the others are Pope St. Gregory I, Pope St. Nicholas I, and St. John Paul II, of happy memory.
Speaking of popes, it’s Leo we have to thank for giving us a greater understanding of what’s referred to as “Petrine primacy” – the fundamental Catholic principle that it’s the Bishop of Rome who rules over the whole Church, in communion with the bishops of the world, but standing as a distinct head over them. It was something Leo preached and wrote about very often, perhaps sensing that the Church needed a strong, visible head at a time when chaos seemed to be the road down which the Western world was headed.
In one instance, Leo wrote:
“Although bishops have a common dignity, they are not all of the same rank. Even among the most blessed apostles, though they were alike in honor, there was a certain distinction of power. All were equal in being chosen, but it was given to one to be preeminent over the others. . . . [So today through the bishops] the care of the universal Church would converge in the one See of Peter, and nothing should ever be at odds with this head”
To mention a last bit about his legacy, Leo was made a Doctor of the Church – one of just 36 individuals whose contributions to the Church throughout history are of special worth – by Pope Benedict XIV in 1754 – who many may remember was also the one who rescued St. Peter’s Basilica from collapse – and it was another Pope Benedict – Benedict XVI – who devoted one of his Wednesday audiences to the great pontiff back in 2008.
The latter Benedict praised Leo for his prolific sermons and writings – 100 sermons and 150 letters still exist to this day – and also gave nods both to his talent as a pastor, and for the deep faith in Jesus Christ which filled the veins of his papal ministry. Quite a pope. Easily one of the best ever, and definitely in my personal top 5.
To take us out this week, here’s another gem from St. Leo, this one on the virtues in fasting and moderation:
“No one is so holy that he ought not to be holier, nor so devout that he might not be devouter. For who, that is set in the uncertainty of this life, can be found either exempt from temptation, or free from fault? Who is there who would not wish for additions to his virtue, or removal of his vice? Seeing that adversity does us harm, and prosperity spoils us, and it is equally dangerous not to have what we want at all, and to have it in the fullest measure. There is a trap in the fullness of riches, a trap in the straits of poverty. The one lifts us up in pride, the other incites us to complaint. Health tries us, sickness tries us, so long as the one fosters carelessness and the other sadness. There is a snare in security, a snare in fear; and it matters not whether the mind which is given over to earthly thoughts, is taken up with pleasures or with cares; for it is equally unhealthy to languish under empty delights, or to labour under racking anxiety.”
Pope St. Leo the Great, pray for us!