Today’s pope question arose twice in one day recently, so I feel it is worth answering. I was asked what sort of manuscripts I’ve been studying, and I said that I’m currently looking into Late Antique Papal Letters; or Papal Letters from the Roman Empire (one from Siricius [pope 384-399], four from Innocent I [401-17], one from Zosimus [417-18], two from Celestine I [422-32]). These particular letters whose transmission I’m studying are, in fact, genuine.
But how can we know?
I think the first thing to deal with here is: Why are all early papal letters suspect? My guess is: a. The Donation of Constantine and b. Pseudo-Isidore. The Donation of Constantine is the famous ninth-century forgery that gave Pope Silvester (pope 315-335) all sorts of temporal power that no pope had before the Central Middle Ages. Lorenzo Valla, in one of the great moments in humanistic study and the history of philology, proved it a forgery in 1440. Pseudo-Isidore is also ninth-century, but of a different ilk. By ‘Pseudo-Isidore’, scholars of canon law mean a group of forgers (or maybe their forgeries) in mid-ninth-century Frankish lands (c. 844?) who produced a vast array of forged papal decretals (papal letters universally binding in canon law) from very early popes right up to when we have actually papal letters.
These two factors, I imagine, are why people think all early papal letters are forgeries; most of them are.
However, it is entirely reasonable to assume that letters written by Bishops of Rome would survive to posterity from the ancient world. This can be drawn first of all from analogy. Other western bishops left behind their correspondence, most famously St Cyprian, St Ambrose, and St Augustine, but we also have letters of, for example, Aurelius of Carthage. Eastern episcopal correspondence also survives, such as St John Chrysostom, St Basil of Caesarea, and St Athanasius. Indeed, the Bishops of Alexandria have left us many letters, most famously their yearly ‘festal letters’ that inform the Egyptian clergy of the date of Easter for the year and deal with some internal affairs and give a bit of exhortation.
If bishops from Carthage, Hippo, Milan, Alexandria, Constantinople, and Caesarea are involved in the business of ecclesiastical letter-writing in Late Antiquity, why not bishops of Rome?
It is also reasonable to assume that people would be interested in what Roman Bishops had to say. After, Canon 6 from the Council of Nicaea (325) says:
Let the ancient customs in Egypt, Libya and Pentapolis prevail, that the Bishop of Alexandria have jurisdiction in all these, since the like is customary for the Bishop of Rome also. Likewise in Antioch and the other provinces, let the Churches retain their privileges. And this is to be universally understood, that if any one be made bishop without the consent of the Metropolitan, the great Synod has declared that such a man ought not to be a bishop. If, however, two or three bishops shall from natural love of contradiction, oppose the common suffrage of the rest, it being reasonable and in accordance with the ecclesiastical law, then let the choice of the majority prevail.
Rome was Metropolitan of Suburbicarian Italy and chief episcopal see in the western, Latin-speaking Mediterranean. Due to actions of Constantine and then a long series of disgruntled provincial clergy, the Bishop of Rome in the fourth and fifth centuries developed into an arbiter in disputes and court of appeal. People will have wanted to keep what this guy had to say.
So much for the theoretical grounding as to why it is inevitable that people will have kept and transmitted genuine papal letters.
How can we tell, though??
Not to go into the gory details, one question is how early the collections and manuscripts that contain a letter are. Is it in collections from the late fifth or early sixth century? Or does it not appear until the ninth or tenth century?
The next question is: How does the material match the context of the letter? For example, one of the Leo forgeries is all about the rights of chorepiscopi in Gaul and Germany. This was an issue in the 800s, not the 400s, not least because there wasn’t really an established episcopate of any sort in Germany at the time. But when Siricius makes references to the Council of Ariminum (Rimini, 358) and the canonical precedent established at the time, it seems genuine.
Leo the Great writes about Manichaeans in Ep. 7, and we have corresponding evidence from his sermons, from imperial laws, from the Chronicle of Hydatius and the Chronicle of Prosper that Manichaeans were an issue at that time. It is reasonable to assume that Leo would have written about/against them in his letters.
Of course, one will protest, isn’t contextualisation what makes a good forgery? Well, yes, but I can assure you that it is the burden of the many smaller references that help tip the scales, as well as references to canonical practice that would change over time.
Then there is style and terminology. This is harder. Even popes with distinctive personal styles like Leo the Great look an awful lot like their predecessors — a problem facing the identification of a fragment in one ms, is it Leo or Boniface I? Nonetheless, different popes have subtle differences, although it can be hard to spell it out. I do find, though, that Innocent I does not write the same as Leo the Great. I promise.
And don’t forget the seruus seruorum Dei rule — if it turns up in a papal letter before Gregory the Great (590-604), it’s either an interpolation or the whole letter’s a forgery.
I hope this helps. I promise that I’m not mistakenly reading a bunch of forgeries. Early papal letters are a vastly understudied and misunderstood resource for the historian of Late Antiquity, so casting aside the forgery burden is an important task so we can get down to studying the real documents.