ROME — When Pope Francis visits the northern Italian city of Turin in June, his outing will once again shine a spotlight on Catholicism’s most famed — and also most debated – artifact: the Holy Shroud.

The Shroud of Turin is a centuries-old, 14-foot-long linen cloth carrying the image of a man who suffered injuries in a manner consistent with crucifixion. Devotees venerate it as the burial cloth of Jesus Christ himself, though there’s long been a lively scientific and popular debate about how old the cloth really is and how, exactly, its image was formed.

And now, for the fourth time since 2000, the shroud is on public display until June 24 in Turin’s cathedral, and Pope Francis will venerate the shroud during his June 21-22 visit to the city.

But even with a papal visit on the horizon, some still doubt the shroud’s veracity.

Joe Nickell, for instance, who describes himself as the world’s only full-time paranormal investigator, says it’s a hoax from the Middle Ages cooked up either to sell relics or to impress infidels.

“What I or anyone else believes about the Shroud of Turin is beside the point,” Nickell told Crux via e-mail. “At issue should be the evidence, and on that basis science has shown the Shroud of Turin to be — like so many alleged relics — a medieval fake.”

Perhaps the most powerful evidence that the shroud is inauthentic is radiocarbon dating by three laboratories that showed it was created in the 13th or 14th century.

Yet the Rev. Andrew Dalton, a Legionaries of Christ priest who’s a shroud expert, told Crux that although the Church respects the autonomy of the scientific community, there are details that simply couldn’t have been forged centuries ago.

Dalton describes the shroud as the “natural effect of a supernatural event.”

When Francis visits Turin, he’ll likely maintain the same caution as previous popes – acknowledging the shroud as an important relic and source of faith, without passing judgment on the scientific controversy.

Pope Benedict XVI, for instance, called the shroud a “winding-sheet that was wrapped round the body of a man who was crucified, corresponding in every way to what the Gospels tell us of Jesus.”

Pope Pius XII in 1936 called it a “holy thing perhaps like nothing else,” and during a 1980 outing to Turin, Pope John Paul II used the word “relic,” saying the shroud was a “distinguished relic linked to the mystery of our redemption.”

No matter what the current or any other pope says, it almost certainly won’t end the debate between believers and skeptics.

Nickell, the skeptic, amasses multiple arguments to cast doubt on the veracity of the shroud:

  • It’s contrary to Jewish burial practices at the time of Jesus, he said, which involved multiple linen cloths of plain weave — rather than the medieval herringbone pattern of the Turin cloth — plus a washed body and quantities of burial spices suspiciously absent from the “relic.”
  • It lacks any provenance before the mid-14th century, at which time a bishop’s investigation claimed it was part of a faith-healing scam. The bishop said it was the work of a confessed artist.
  • It exhibits numerous flaws, such as the hair falling straight down, as would be the case for a standing, not a reclining, body; the hands placed discreetly over the loins (again contrary to Jewish practice), the “blood” stains remaining suspiciously red and picture-like.
  • The “blood” has failed a battery of tests by internationally known forensic serologists, and subsequent analysis claimed it was tempera paint containing red ocher and vermilion pigments — pigments that were also found throughout the image (but not off-image) areas. Proponents lack any viable hypothesis for the image formation, and have dismissed re-creations that others have found convincing.
  • The cloth was radiocarbon dated by three laboratories (Oxford University, the University of Arizona, and the Swiss Federal Institute of Technology, under the auspices of the Pontifical Academy for Sciences) to circa 1260–1390. Proponents nevertheless claim the sample taken for dating came from a “medieval patch,” but this is contradicted by the textile experts who took the samples.

For everyone convinced by those scientific points, there’s someone else who finds them bunk.

Dalton, the priest, insists that the image on the shroud, which is a photographic negative, is absolutely unique and could not have been faked.

“No paint, no UV rays, no infrared, varnish, or rub in any laboratory can duplicate what we have today,” he said in a phone interview on the eve of a trip to Hong Kong and Canada to speak about the shroud.

Dalton also insists that the samples dating to the Middle Ages were taken from patches added to the cloth after it was damaged by a fire, and he said that other experts caution that ancient cloths often date later in radiocarbon analysis than their actual origins due to bacterial contamination.

But it’s not just Catholics who find the shroud convincing.

Barrie Schwortz, an Orthodox Jew based in Los Angeles, is a professional photographer who was responsible for scientific and documentary photography during the first examination of the shroud in 1978.

Schwortz told Crux that the cloth is the only archaeological artifact on the planet where “science and faith live side by side on the same piece of cloth.”

Despite being the most studied artifact in history, Schwortz said, modern science is still unable to explain the image or how it was made.

That said, he believes several factors point in the direction of authenticity:

  • Sophisticated spectral and chemical analyses by the Shroud of Turin Research Project in 1978 found no traces of paints, pigments, or binders, or any evidence of artistic involvement on the shroud.
  • As a photographer, he described the image itself as the most interesting and convincing fact: “It has properties unlike any other image I have ever seen,” he said, and no one in the past 40 years has been able to duplicate it or create any image with the same chemical and physical properties.
  • Highly accurate forensic representations on the shroud were far beyond the knowledge of any medieval forger, Schwortz said. Blood flows are natural and not applied to the image by hand, but soaked into the cloth when it was in contact with a body.
  • The bloodstains were chemically tested and determined to be actual blood and not paint or pigment.

Dalton also asks why, if the cloth is actually a medieval forgery, scientists have been able to find particles of dirt from Jerusalem in the nose, the knees, and the soles of the feet.

Dalton notes that the late Rev. Giulio Ricci, president of the Vatican’s Roman Center for Study of the Holy Shroud, catalogued every single blow depicted on the body of the man shown on the cloth and concluded that there’s a directionality to the wounds suggesting two assailants, and that the radius of the blows is different because the men were of different heights.

“It’s impossible for me to believe that someone in the 1300s was thinking in those terms,” Dalton said.

Schwortz says the back-and-forth between believers and skeptics probably will never be resolved, in part because the shroud challenges many people’s core beliefs and makes some of them very uncomfortable.

“I realize that that is not a dogma of the faith,” Dalton told Crux. “The Church doesn’t require anyone to believe in it, so if the shroud was proven fake tomorrow, it wouldn’t shake the foundations of the faith.”

Organizers of the exhibition say they expect at least 1 million people from throughout the world to visit during the two-month-long public exposition; close to 850,000 people have already registered to do so through the official website, www.sindone.org.