The Journey of the Holy Shroud of Turin

The team of Italian scientists who utilized new X-ray dating techniques to date the Shroud to the time of Christ’s death have used the same techniques to chart its probable geographical course afterward.

Pope Francis leaves after praying in front of the Shroud Turin, June 21, 2015 in Turin's cathedral.
Pope Francis leaves after praying in front of the Shroud Turin, June 21, 2015 in Turin's cathedral. (photo: Alberto Pizzoli / AFP via Getty Images)

BARI, Italy — Six months after a group of Italian scientists made a breakthrough discovery using new X-ray dating techniques to show the Holy Shroud of Turin dates back to around the time of Christ’s death and resurrection, the scientists have now used the same experiments to determine the probable geographical route of the priceless relic.  

The six-member research team estimated the natural aging for different localities where the Shroud could have been kept before its European history, and then compared the result with the experimental value obtained by X-ray.  

The researchers then found that the most likely route that best matched the X-ray measured natural aging of the Shroud was Jerusalem-Beirut-Constantinople-Lirey-Chambéry-Turin, although other paths cannot be totally excluded. The findings were published in a peer-reviewed paper on Sept. 28.  

In this Oct. 4 interview with the Register, chief researcher Liberato De Caro of Italy’s Institute of Crystallography of the National Research Council in Bari discusses the findings in more detail and whether a judgment on the authenticity of the Shroud can be definitively made. He also contends that, according to their research, the Holy Shroud of Turin is currently being preserved in conditions in Turin cathedral not ideal for the visible image on the fabric, and that a much lower temperature should be used for the controlled atmosphere of the reliquary.  


Dr. De Caro, earlier this year, you published research using new techniques which showed that the Holy Shroud does coincide with Christian tradition by dating back to around the time of Christ’s death and resurrection. What do your latest findings tell us?  

The Turin Shroud’s fabric is made by linen. Natural aging of linen is influenced by temperature and relative humidity. The dependence of natural aging on the temperature is strongly non-linear. All those who have obtained a driving license know that speed and stopping distances don't increase at the same rate. Small increases in speed result in bigger increases in stopping distances. This is a typical non-linear effect. The same thing happens for temperature and natural aging: A small increase in temperature causes a big increase in the linen aging.  

In my previous works, the natural aging of linen has been calculated by using secular average values for the temperature and relative humidity. But this approach is more suitable for linen fabrics kept in deep underground tombs where daily, monthly, and seasonal temperature variations are almost completely filtered out.  

For example, if we visit a cave in summer, the temperature inside will be much lower than outside. Actually, it is nearly constant for all the year. Since it is more probable that, for all its history, the Shroud should have been kept either in churches or in other private buildings, not underground, the natural aging of its linen should have suffered seasonal variations of temperature.  

In the last research we have taken into account monthly variations of temperature and relative humidity for calculating the natural aging of linen, leading to theoretical predictions more reliable for fabrics kept in private buildings, churches and not underground. 


Can you explain in more detail and in layman’s terms how your research can be applied to the geographical path of the Shroud and how it helps to confirm its authenticity? 

We have an experimental estimate of the natural aging of the linen of the Shroud, obtained by X-rays. This aging is influenced by monthly temperatures and relative humidity of the localities where the relics could be kept over the centuries.  

Spending the summer in the heat of Egypt is not the same as spending it in Iceland. Our skin, without any protection, will be very different at the end of summer. If after an entire summer, a friend of ours is not tanned at all, he hardly spent it in Egypt. Similarly, linen cellulose ages much faster if the environmental temperature and relative humidity are much higher.  

We know the European history of the Shroud, where it has been kept. If it has 2,000 years, as deduced by the X-ray dating, where could it have been kept? We can theoretically estimate the natural aging for different localities where the Shroud could have been kept before its European history and compare the result with the experimental value obtained by X-ray. The best match will indicate the more probable localities, the more probable geographical path that the Shroud would have done during the centuries before its European history.  


Exposition of the Holy Shroud April 18, 2015 in Turin.(Photo: Miqu77)Copyright (c) 2015 miqu77/Shutterstock. No use without permission.

Your findings suggest the Holy Shroud took the Jerusalem-Beirut-Constantinople-Lirey-Chambéry-Turin path. What other route possibilities are there, and do we know why the Holy Shroud took these possible particular routes? 

Many scholars think that the ancient traditions of “acheiropoieton” images of Jesus Christ, i.e., icons “made without hands,” could be related to the Shroud. There are historical sources for these images present in several localities. The most important are Memphis (Egypt), Edessa (today, Şanliurfa, in Turkey), Camulia (Cappadocia, Turkey), Beirut (Lebanon) and Constantinople (today, Istanbul, in Turkey).  

The average annual temperature at Memphis is greater than 22 Celsius [72 Fahrenheit]. Instead, at Camulia it is less than 10 Celsius [50]. This causes an enormous difference in terms of natural aging, due to the non-linear effects of temperature on cellulose aging. 

For each locality, where there is an ancient tradition of an acheiropoieton image of Jesus Christ, we can calculate the alleged contribution to the natural aging of the Shroud. Comparing these theoretical evaluations with the X-ray measured value, we can have an indication on the historical/geographical path that the Shroud could have done before its known European history.  

The Jerusalem-Beirut-Constantinople-Lirey-Chambéry-Turin path is the one that best matches the X-ray measured natural aging of the Shroud, even if some other paths cannot be fully excluded. Going into the details of this path, in Jerusalem, the Shroud could not have been kept for long because of the outbreak of the revolt of the Palestinian Jews against Rome.  

Indeed, according to Eusebius the Christians of Jerusalem escaped to Pella, bringing with them all the relics and main religious objects. Their escape occurred before the destruction of the Temple (year 70), probably at the beginning of the revolt. In particular, the Icon of Beirut was described as an image representing the entire body of Jesus Christ — with the wounds endured during the Passion — by Anastasius the Librarian in the year 873, who also narrated its origin and travel from Jerusalem to Beirut, where it remained until the year 975.  

After this period, this icon was brought to Constantinople where, if it coincides with the Shroud, it remained until 1204 — the year of the Sack of Constantinople during the Fourth Crusade, when it was allegedly stolen by crusaders.  

The Shroud appeared publicly for the first time in Europe, in 1354 in the hands of Geoffroy de Charny. In 1350, he built a small church in Lirey (France), where he was the lord, with the purpose of hosting several relics, among which the Shroud was likely included. In 1453, his granddaughter Marguerite gave the Shroud to the Savoy, a noble family based in Chambéry, where it was damaged by fire in 1532. It was moved to the new Savoyard capital, Turin, in 1578, where it is still kept.  

Calculating the natural aging of linen for each of the above historical/geographical steps, we obtain a theoretical value that can be compared with experimental value obtained by X-ray. The above-described path is the more probable because it gives a prediction for the natural aging of linen, which best matches the experimental value obtained by X-rays, even if other possibilities cannot be fully excluded. 


You mention the environment in which the Holy Shroud is now stored in Turin. Can you explain this aspect more for us and how it helps determine the ageing process of the Shroud and therefore its probable age? 

Since 2000, the Shroud has been preserved in a reliquary with a controlled atmosphere of 99.5% argon and 0.5% oxygen, at equalized atmospheric pressure, at 50% relative humidity, and a temperature of 19-20 Celsius [66-68]. A 100% oxygen-free environment favors the increment of anaerobic organisms on the Shroud. Therefore, some oxygen has been added in the controlled atmosphere of the reliquary where the Shroud is kept. Moreover, fully dried environments allow shrinking of textile fibers. To avoid this shrinking effect, some water vapor has been added to the controlled atmosphere. But, in presence of water vapor, the value of temperature at which the Shroud is kept today, according to our calculations, could be too high.  

Following the previous example, it’s like always living in Egypt: it would become impossible not to see that one’s skin becomes more and more tanned, although this is due to ultraviolet rays and not to room temperature. But this simple example immediately clarifies what are the possible dangers for the Shroud. Indeed, natural aging causes also yellowing of the linen, allowing the formation of chromophores (color centers) just in correspondence of the chain breaks of the polymeric structure of the cellulose constituting the linen. This, in turn, should cause a lowering of the image contrast of the image of the Man of the Shroud.  

According to our estimates, to preserve the visibility of this image, as long as possible in the next centuries, a much lower temperature of the controlled atmosphere of the reliquary should be used.  


Do your findings effectively bring to an end the debate over the authenticity of the Holy Shroud, in your view? 

Since there are two different dating techniques that on the Shroud give different results (Carbon-14 and X-rays), in principle, it would be necessary to have further experimental tests to close this debate.  

In any case, there are many other traces in history (coins, Christ’s icons, paintings, etc.) which, indirectly, attest the existence of the Shroud well before the 14th century. If it had been any other object of the past, all these indirect proofs would have already been sufficient to attest to its authenticity. Instead, for the Shroud the situation is different because many scientists, even editors and reviewers, hinder the publication of studies concerning the Shroud. Some of them are strongly influenced by their rationalism and their conclusions are biased. But many others do it as an authentic service to knowledge, as they take it for granted that the Shroud is a medieval forgery.  

Therefore, the fact that the Shroud could be the burial sheet of Jesus Christ is considered only a myth to dispel. Moreover, it is often affirmed that science cannot deal with arguments concerning the Christian faith, like the Resurrection of Christ, because it is not a physical phenomenon allowed by the physical laws that we have discovered, and it cannot be reproduced in a laboratory. But even the Big Bang, the birth of the universe, cannot be reproduced in the laboratory, and it cannot be explained by the physical laws that we have discovered until now. In fact, to understand the birth of the universe and why ordinary matter is made just as it is, we are still waiting for new revolutionary theories in physics. Even if the Big Bang cannot be reproduced in a laboratory, even if it is not still explained by our scientific knowledge, the first instants of its evolution are extensively studied by many researchers in the world. It could be argued that the birth of the universe has left a trace: the cosmic microwave background radiation, that can be studied. But how can we exclude with certainty that the image of the Man of the Shroud cannot be a consequence of the Resurrection? If a researcher studies the image visible on the Shroud, to have possible indications about the Resurrection, is considered by many colleagues as a visionary, and his study is with certainty hindered by almost all scientific journals. In some ways, he lives the same experience Paul lived at the Areopagus: “When they heard about resurrection of the dead, some began to scoff, but others said, ‘We should like to hear you on this some other time.’” 


How did your research into the Holy Shroud come about and could you give us more details on who else is on your research team? 

Interest in the Turin Shroud was born, by chance, during a 2016 conference where I met Giulio Fanti, professor at Padua University, who was presenting the results of his long-lasting study. Since then, a fruitful collaboration has been born with him that has also led to this last work. Other authors of our last research on the Shroud (downloaded for free here), are some of my colleagues of the Institute of Crystallography of the National Council of Research (IC-CNR), in Bari (Italy), where I work: Teresa Sibillano and Cinzia Giannini.  

In that first meeting with Professor Giulio Fanti, in 2016, there was also Cinzia Giannini, who is the current director of the IC-CNR Institute. I have been working with Cinzia for the last 32 years, really many! Another of the authors is Professor Emilio Matricciani, engineer of the Polytechnic of Milan (Italy). And finally, there is César Barta, a Spanish physicist, now retired, and also an expert in Shroud studies. 


Is there anything more you have discovered about the Holy Shroud in your research that has yet to be published, and what future projects do you have planned? 

We are planning other X-ray measures on linen fibers to better understand the natural aging of linen and how it can be eventually influenced by other causes. Moreover, the Shroud is not the only linen relics associated to Jesus Christ. Among the wonders that the Gervase of Tilbury describes in an early 13th-century encyclopedic work, there is the Holy Face of Lucca, a crucifix, still venerated in Lucca (Italy) which, according to what Gervase writes, would actually be a reliquary. Indeed, according to him, inside it was kept the sheet used to carry Jesus to the sepulcher when he was taken down from the cross. This is not the Shroud. It should be a different relic used only for carrying Jesus to the sepulcher.  

A recent radiocarbon dating of the crucifix has indicated that it is very old, of the eighth century. It would therefore be the oldest wooden sculpture in the Western world. Moreover, it has just the shape of a reliquary on its back. Therefore, it cannot be excluded that it could be a copy of a more ancient wooden reliquary, which has been lost, perhaps because it was fully ruined.  

Some medieval historical sources attest the presence of a sudarium kept in Lucca, giving indications where it should be searched. If it is really kept where it has been described and if it is of linen, it could be dated in the same way as the Shroud. Also the Sudarium of Oviedo, in Spain, a linen bloodstained piece of cloth, always related to the Passion of Jesus Christ, could be dated with the same X-ray technique, in order to compare the dating results with radio-dating already made.  

All this research could allow us to discover new relics related to Jesus Christ but also discard false ones. To reach these important discoveries, we must have the will to know the truth fully, as only the truth will set us actually free (John 8:32).