The Church’s Tradition relates that Saint Peter came to Rome, where he died a martyr during the persecution of Nero, being crucified upside down, and was buried in the Vatican near the site of his glorious martyrdom. On his tomb, which soon became an object of veneration, the first Vatican Basilica was built at the behest of Constantine in the fourth century.
This tradition has been confirmed by the investigations of science. Professor Margherita Guarducci has studied the issue deeply, working since 1952 in the substructure of the Vatican Basilica, managing to decipher the ancient graffiti under the Altar of the Confession in 1958 and finally to identify the relics of St. Peter in 1964 (cf. M . Guarducci, The Tomb of Peter: An Extraordinary Story [Milan: Rusconi, 1989]; The Relics of Peter in the Vatican [Rome: Government Printing Office and National Mint, 1995]; The Keys on the Rock (Casale Monferrato: Piemme, 1995]; The Primacy of the Roman Church [Milan: Rusconi, 1991]). Now, “if Rome was the center of the universal Church, the focal point of this center was the tomb of Peter” (Guarducci, The Tomb of Peter, p. 10).
In particular, two sources, extremely authoritative and very close to the facts narrated, prove that St. Peter was martyred in the Vatican. They are St. Clement of Rome and Tacitus.
At the end of the first century, Pope St. Clement, speaking of the persecution of Nero (A.D. 64), certifies that the Christians on that occasion gathered around the Apostles Peter and Paul, to attain the strength needed to pass the test (Epistle to the Corinthians, I, 5-6).
The great Roman historian Tacitus, towards the end of the second century, attests that Nero, after the fire of Rome (A.D. 64), having been accused by the populace of provoking it, wanted to blame it on the Christians and unleashed a fierce persecution against them. This came to its conclusion, according to Tacitus (Annals, XV, 44), in the circus of Nero’s own gardens in the Vatican, the only place of entertainment remaining in Rome after the fire of 64. Here, many Christians perished.
In Rome, during the pontificate of Pope Zefirinus (199-217), a learned Roman ecclesiastic named Gaius took issue with Proclus, the leader of the Roman Montanists. Since Proclus, to devalue the authority of the Roman Church, boasted of the presence in Asia Minor of various famous tombs of the apostolic age (the tomb of the Apostle Philip and his four daughters), Gaius opposed to those graves the “trophies” or glorious tombs of the Apostles Peter and Paul, existing respectively in the Vatican and on the Ostian Way. The words of Gaius are recorded by Eusebius of Caesarea, the famous church historian, who wrote in the first half of the fourth century (Historia Ecclesiastica, II, 25, 7).
St. Jerome in De viris illustribus, composed in 392, says that Peter was buried in the Vatican and was venerated there by the faithful of the whole world. Moreover, in the Liber Pontificalis of the sixth century we read that Peter “was buried on the Via Aurelia...at the place where he was crucified...in the Vatican.”
On June 28, 1939, Pope Pius XII gave the order to lower the floor of the Vatican Grottoes to allow archeologists to study the issue of the tomb of Peter. It was the beginning of an amazing feat. The excavations lasted about ten years (1940-1949) and ended on the eve of the Holy Year of 1950. The official report of them came out in November 1951.
The excavations led to the discovery, below the Vatican Basilica, of a vast necropolis of pagan times with successive Christian elements. The extreme western area of the necropolis is located under the dome of Michelangelo, that is, under the Altar of the Confession. Under this altar, the excavations revealed the existence of a series of superimposed monuments. Starting from the present-day altar (of Clement VIII, 1594) and proceeding downward, there are: the altar of Callistus II (1123); the altar of Gregory the Great (590-604), which remained included in the subsequent altar of Callistus; the monument erected by Constantine predating the Basilica (about 321-326) and, inside the Constantinian monument, a funerary aedicule (end of second to beginning of third century): the so-called “Trophy of Gaius” (Guarducci, The Relics of Peter, pp. 15 ff.).
The west end of the cemetery includes a fairly large area, called by archaeologists “Field P.” It is bordered by a wall, called the “Red Wall” because of the color of the plaster that covered it. At the center of the “Red Wall” is a semicircular niche and, a bit higher up, a small wall, called “Wall g,” which is covered on its north side by a forest of graffiti. The “Red Wall” with the semicircular niche is the backdrop to the “Trophy of Gaius,” the votive altar that Christians erected in the second century over the earthen tomb in which the body of St. Peter was buried in 64. The Trophy takes its name from the Roman priest Gaius of the third century (discussed above), who asserted that the tomb of Peter is in the Vatican in Rome.
Under the Trophy of Gaius, archaeologists appointed by Pope Pius XII found the place of the primitive burial (earthen tomb), but they found it empty. Why? This is explained by considering that at the beginning of the fourth century, Constantine built on the site of the ancient Trophy of Gaius a large basilica with five naves, whose altar was located exactly above the grave of the Apostle. The same Emperor had already had the bones of St. Peter gathered from the damp earthen tomb and, wrapped in a precious fabric of purple and gold, had them placed in a dry and fitting marble niche set in a wall (Wall g) that stood alongside the primitive burial place. The north part of Wall g was covered by a “wild forest” of graffiti, among which stood out also the names of Christ, Mary and Peter, but the authors of the excavations were not able to decipher the tangle of writing.
At the conclusion of the work, in any case, the first scholars had come to establish that the various monuments built upon the altar of the Confession on the initiative of some of the popes, all rest, overlapping, on the ancient monument of Constantine. In short, the excavations ordered by Pius XII archaeologically confirmed what Tradition already taught: that the tomb of St. Peter is still under the Papal Altar. In his Christmas message of 1950, Pope Pius XII, therefore, announced to the world: “Was the tomb of St. Peter really found? To this question the final conclusion of the work and studies responds with a clear yes. The tomb of the Prince of the Apostles has been uncovered. A second issue, subordinate to the first, concerns the relics of the saint. Were they discovered? At the edge of the tomb the remains of human bones were found, however, it is not possible to prove with certainty that they belonged to the mortal remains of the Apostle.”
Therefore the tomb of Peter was found with certainty, but not with equal certainty the bones of the saint. The merit of the discovery and identification of them can be attributed mainly to Margherita Guarducci, who, beginning to be interested in the Vatican excavations, brought with her the method that she had long since adopted and refined, namely that of rigorous scientific research, having been for many years an archaeologist by profession and a university professor.
The relics of the Prince of the Apostles were not found even in the marble niche of Wall g where Constantine had had them placed in the fourth century (on the right of the Trophy of Gaius, built in the second century over the primitive grave, or earthen tomb, where St. Peter was buried in A.D. 64). Why?
In 1941, while Monsignor Kaas, who was personally monitoring the progress of the work, made the usual inspection tour of the excavations in the evening (after the Basilica closed) accompanied by “Sampietrino” Giovanni Segoni, he noticed that in Wall g, in the midst of various debris, some human bones were visible. Their presence had escaped the notice of the four scholars who worked at the excavation during the day. But they did not escape the vigilant and careful eye of the German Monsignor. With a sense of respect for the remains of the deceased, Monsignor Kaas decided to separate the bones from the debris, and to have Segoni put them in a wooden box that the same Segoni and Monsignor Kaas then deposited in a storeroom of the Vatican grottoes. “With this [writes Guarducci] Monsignor Kaas saved, without knowing, the relics of Peter” (Guarducci, The Tomb of Peter, p. 84).
In 1952 Professor Guarducci asked to visit the excavations. Her desire was to see with her own eyes an inscription that appeared in a drawing published by the Jesuit Father Antonio Ferrua on January 5, 1952 in the magazine La Civiltà Cattolica and on January 16 in the Rome newspaper Il Messaggero. It was a reconstructive drawing of the aedicule erected in honor of St. Peter in the second century. To the right a Greek inscription was drawn on the wall: PETR / ENI. Guarducci thought that ENI could be a contracted form of ENESTI (“is inside”), whence resulted the sentence “Peter is here, here he lies.”
It was necessary, however, to determine whether the sentence continued towards the right, in which case the meaning could be different. However, when the professor, led by Eng. Vacchini, was able to visit the area of the excavations, she was deeply disappointed: where the very interesting inscription was supposed to be, there was a rather large gap in the plaster. The missing fragment was found by Father Ferrua, who, for unknown reasons had taken it to his cell and, once it was known, had to return it to the Vatican in 1955 by order of Pope Pius XII. Guarducci could then study it and saw that the top line of the inscription inclined downwards, preventing the continuation of the second line. Thus the reading ENI and the subsequent interpretation of the professor were confirmed. The epigraph thus acquired a very great value (Guarducci, The Relics of Peter, pp. 46-50).
Meanwhile, in 1953, Guarducci had begun to study the numerous graffiti inscribed on Wall g, of which previous scholars were able to decipher only a small part. Guarducci herself relates the events thus: “While I puzzled to find a way into that savage forest [of graffiti], it occurred to me that maybe it would be helpful to know if something else had been found in the niche below, besides the small remnants described by the excavators in the official report. By chance, Giovanni Segoni was nearby, who had recently been promoted to the lead position of the ‘Sampietrini.’ I directed my question to him…, and he answered without hesitation: ‘Yes, there must be something else, because I remember gathering it with my own hands. Let’s go see if we can find it.’ He then led me to the storeroom of bone fragments....I went in behind Segoni for the first time into that room. There, among crates and baskets filled with bone fragments and other various materials, lying on the ground was the box that the same Segoni and Monsignor Kaas had deposited more than ten years before....A note, tucked between the box and the lid, very moist but still perfectly readable, declared that the material came from Wall g. Segoni told me that he had written it himself....I thought it appropriate and necessary to immediately take the box to the office of Eng. Vacchini and there...the box was opened and we extracted the contents. We found a certain amount of bones, of a distinctly clear color, mixed with soil..., fragments of red plaster, and tiny reddish fragments of cloth woven with gold thread....I have to say... [continues Guarducci] the idea had obviously already flashed in my mind that the niche of Wall g was originally intended to house the relics of Peter....But then, before the recovered remains, I felt strongly skeptical...” (The Relics of Peter, p. 85-87).
The famous professor Venerando Correnti was chosen to be the anthropologist who studied the bones contained in the box. Here is the result of his studies: the bones belonged to a single individual, male and of a robust constitution, whose age ranged between sixty and seventy years; they constituted about half of the skeleton, representing all parts of the body except the feet; some of the bones showed traces of reddish color that made one think of a fabric that had enclosed them. All of these elements corresponded perfectly to St. Peter.
In the meantime, since Pius XII had unfortunately passed away in 1958, John XXIII took up the question of the tomb and relics of Peter, but Guarducci notes that “he [John XXIII], however, lacked that innate impulse of love for Rome and the vision of that vast cultural horizon that had inflamed Pius XII with an extraordinary interest in the subterranean area of the Vatican Basilica” (The Relics of Peter, p. 73). Nevertheless, the research continued. All the scientific data gathered since then, together with the epigraph “Peter is here” from the Red Wall, made it possible for Guarducci to be able to announce to Paul VI on November 25, 1963, that, with great probability, the relics of St. Peter were finally found.
Meanwhile, the scientific investigations were extended to the commercial and chemical disciplines (conducted by Professor Maria Luisa Stein and Professor Paolo Malatesta from “La Sapienza” University of Rome) and yielded the following results concerning the fabric: it was a very fine cloth dyed with authentic and valuable Tyrian purple; the gold was authentic and very fine: it was the same type of purple fabric interwoven with gold in which the bodies of the Emperors were wrapped!
All of this confirmed that the body buried in the earthen tomb and then wrapped in purple and gold inside the Constantinian niche was that of the Prince of the Apostles, St. Peter! Even the earth which encrusted the bones was subjected to a petrographic examination by Professors Carlo Lauro and Giancarlo Negretti: it was sandy marl very similar to the soil in Field P which confirmed the origin of the bones as coming from the underground niche or earthen grave that lay under the Trophy of Gaius of the second century.
At the conclusion of these and other findings made in the following years by other scientists, Paul VI announced to the faithful on June 26, 1968, that the bones of St. Peter had been found and identified.
However, Guarducci found in the speech of Paul VI some reluctance, inaccuracies, and contradictions, due to the old anti-Roman and anti-Petrine prejudice and the new ecumenical spirit of the “subsistit in.” In fact, the text reads: “The research, verifications, discussions, and controversies will not have ended...; we have reason to believe that only a few remnants...of the mortal remains of the Prince of the Apostles have been found.” Guarducci comments: “The phrase...is not very true. In June 1968, the research and verification was now practically exhausted. Everything had been made clear....It also was not very exact to define the relics of the Apostle as a ‘few remnants’...; they were, on the contrary, very abundant: about half of the skeleton in all. This...was the announcement of Paul VI: an announcement that, even if not perfect, was at least at that time sufficient, indeed providential” (The Relics of Peter, p. 118).
On June 27, 1968, the relics of St. Peter were solemnly returned with a notarial deed to the niche of Wall g, where Constantine had had them laid in the fourth century and where twenty-seven years before, Monsignor Kaas had unwittingly removed them, saving them from very probable dispersion.
The fact that the tomb of Peter, the Apostle on whom Jesus said He would build His Church, is in Rome is of paramount importance for the recognition of the Primacy. The Church of Christ is that which is founded on Peter; the tomb and relics of Peter are in Rome, in the Vatican; thus the true Church of Christ is that which is Roman.
Guarducci observes: “It would be...dangerous to forget...that between the unique doctrine of Christianity and those of the other two monotheistic religions [Jewish and Muslim] there also exist deep contrasts, which cannot be glossed over with indifference. The Holy Trinity is a fundamental dogma of the Christian religion, for example. Nothing similar is found in the other two monotheistic religions. One must consider, moreover, that for Christianity the Incarnation of the Son of God...is absolutely essential, and that Incarnation is denied by the Jews....As for Islam, remember that the Muslims shun...the idea that God has a ‘Son’ and that this ‘Son’ could have undergone the infamous torture of crucifixion. The view of Christianity towards the future remains that indicated by Christ Himself. Speaking of Himself in the fourth Gospel as the Good Shepherd (John X, 16)..., the Redeemer said that He has other sheep that are not yet of this fold, but that they will become so. He thinks naturally to the future disciples...who will come...in the course of centuries, to increase the flock gathered by him in Palestine. At the end there will be, He says, ‘one flock and one Shepherd’ (John 10:16). And how will this blessed ingathering take place? ...It will be thanks to the work of the Apostles, and the missionaries who will come after them....And where will be the seat...of the one blessed sheepfold that will house the flock of Christ until the end of time? The answer is easy, and today even easier than in the past: it will be in Rome. It has been proven ...that in Rome...the Catholic Church...is, by a miraculous privilege, physically founded on the authentic relics of Peter. The eyes of all those who think of and honestly work for the future of the Christian world must therefore turn to Rome” (M. Guarducci, The Keys on the Rock, [Casale Monferrato: Piemme, 1995], p. 58-59).
With the discovery of the tomb and bones of St. Peter, the historical tradition of the coming of St. Peter to Rome, his sojourn in the Eternal City as its bishop, and his martyrdom and burial, receives a scientific and irrefutable confirmation consoling to Catholicity. Moreover, this development confirms what the Magisterium of the Church has always maintained: the primacy over the other Apostles that Christ conferred upon Peter is transmitted to the Bishops of Rome in consequence of their succession on the Chair of Peter. And it is for this reason that the opponents of the Roman Church have several times denied the presence of the tomb of Peter in Rome.
Professor Guarducci concludes thus: “On these [the relics of Peter] the Church of Rome is physically founded....Christ, declaring to Peter that He would build His Church upon him..., alludes prophetically to the very Church of Rome and its continuity over the course of the centuries until the last day....Under the altar of the [Vatican] Basilica, we still find, miraculously surviving, the remains of Peter who, by the will of Christ, was, is, and always will be the foundation of His Church” (M. Guarducci, The Relics of Peter, p. 133).