How Does the Catholic Church Investigate Eucharistic Miracles?

A Register Explainer

Detail of a medieval painting in Valencia, Spain, depicts Jesus Christ holding the Eucharist.
Detail of a medieval painting in Valencia, Spain, depicts Jesus Christ holding the Eucharist. (photo: 2018, jorisvo / Shutterstock)

The end of a Mass normally ends with prayer. But on March 5, parishioners in Connecticut were stunned when their pastor paused right after the concluding rites.

St. Thomas Catholic Church in Thomaston, Connecticut, within the Archdiocese of Hartford, may have had a Eucharistic miracle take place during Communion.

“We had something happen. It’s hard to say, actually,” said Father Joseph Crowley, the pastor of St. Thomas.

“God provides. It’s strange how God does that, and it happened today,” said Father Crowley, according to a video.

He went on to explain that an extraordinary minister of Communion, while distributing the Eucharist, noticed that she was running out of Hosts. At a certain point, she discovered that her ciborium — which had been nearly empty — was full again. Father Crowley verified that there were more Hosts in the ciborium at the end of Mass than at the beginning of Communion.

Now, the archdiocese has sent its investigative findings to the Dicastery for the Doctrine of the Faith in Rome.

“Reports such as the alleged miracle in Thomaston require referral to the Dicastery for the Doctrine of the Faith in Rome. The archdiocese has proceeded accordingly and will await a response in due time,” David Elliott, a spokesman for the archdiocese, told CNA May 4.

It’s unclear how long the dicastery could take to respond to the archdiocese’s request, Elliott told CNA.

St. Thomas Church already has a notable history: Blessed Father Michael McGivney, founder of the Knights of Columbus, served as pastor of St. Thomas Church from 1884 until his death at age of 38, on the eve of the Assumption, in 1890.


Connecticut Case

The multiplying-Hosts case prompted the archdiocese to explain the protocols for such investigation. 

On March 28, the Archdiocese of Hartford released a statement regarding “Possibility of Eucharistic miracle in Thomaston being reviewed.”

“As people of faith we know that miracles can and do happen, as they did during Christ’s earthly ministry. Miracles are divine signs calling us to faith or to deepen our faith,” the statement read.

“Roman Catholics experience a daily miracle because every time Mass is celebrated what was bread becomes the Body of Christ and what was wine becomes his Blood. Through the centuries this daily miracle has sometimes been confirmed by extraordinary signs from Heaven, but the Church is always careful to investigate reports of such signs with caution, lest credence is given to something that proves to be unfounded.”

It added, “What has been reported to have occurred at our parish church in Thomaston, of which Blessed Michael McGivney was once Pastor, if verified, would constitute a sign or wonder that can only be attributed to divine power to strengthen our faith in the daily miracle of the Most Holy Eucharist. It would also be a source of blessing from Heaven for the effort that the U.S. Bishops are making to renew and deepen the faith and practice of our Catholic people with regard to this great Sacrament.

“Until the investigation is complete, however, any judgment or further comment would be premature.”

Local television affiliate Fox 61 reported March 29 Archbishop Leonard Blair’s explanation of the process now commissioned.

“I’m sending out an experienced priest who has a knowledge of Church or canon law,” explained Archbishop Blair. “They will follow a procedure to examine what happened, under what circumstances and by whom.”

Archbishop Blair “said the outcome of that investigation will determine if he needs to notify the Vatican.” 

“The guidelines for these kinds of situations do call for me to notify the Congregation [now Dicastery] for the Doctrine of the Faith in Rome,” said Archbishop Blair.

Now, the archdiocese awaits word from the Holy See.

To date, there has never been a verified Eucharistic miracle in the United States.


How Does This Process Work?

Eucharistic miracles are extremely rare. According to the website page on Eucharistic miracles, there have been 139 individual cases of Eucharistic miracles in Church history. Only a few have ever been investigated scientifically.

But in the last 50 years, when a Eucharistic miracle is alleged to have occurred, the Catholic Church generally follows a more standardized investigative process.

  • There has to be absolute certainty of the “chain of custody”; meaning, there is certification that the Eucharistic Host has always been guarded.
  • The bishop or archbishop must state that something highly unusual has happened. 
  • The bishop or archbishop must convene a scientific panel with a principal scientist, credible experts and tests. 
  • The scientific tests must all be in agreement. The Host must be analyzed using different tests that all come to the same conclusion. 
In summary, the scientific panel must unanimously conclude that no preservatives have been used on the Host; that the chain of custody was sound; and that there is no explanation for what has happened to the Host.

Jesuit Father Robert Spitzer, president of the Magis Center and the Spitzer Center for Visionary Leadership and EWTN TV host, explained to the Register the first steps.

“The first thing is that the Eucharist would have to be secured so that the chain of custody would be monitored. The Eucharist should then be put in a container of [holy] water. If it is miraculous, it won’t dissolve. Under normal circumstances, it will dissolve in two days,” Father Spitzer said, referencing possible miracles where a Host appeared to have been transformed into human tissue.

A New York bishop delved into the other steps.

If the preliminary examination does indicate a miraculous event, the pastor of the church where it occurred then contacts the local bishop, Auxiliary Bishop John Bonnici of New York, the pastor of Sts. John and Paul in Larchmont, told the Register.

After a bishop has been notified, he can begin a more formal investigation if he believes one is warranted, as Archbishop Blair has done. Usually, at this point, the Eucharistic Hosts would be photographed. 

“When it comes to Eucharistic miracles, the majority of them have to do with Hosts that have turned to flesh or appear to have blood in them,” Bishop Bonnici noted. “In the case of Hartford, there appears to have been a multiplication of the Hosts. In this case, the bishop will put together a team of investigators with various expertise, like theologians and canon lawyers.” 

“In the case of Hartford, we have the presence of video cameras at our disposal, so they can look at the footage. They can see if the ciborium of the particular Eucharistic minister ever changed hands,” he said.

When the Eucharistic miracle involves a Host that has radically changed appearance — a circumstance not in play in the Connecticut incident — medical scientists would be called upon.

Along with analyzing all relevant physical evidence, witnesses such as priests, sacristans, Eucharistic ministers and parishioners are interviewed. The scientific team also needs to certify the chain of custody, and, as aforementioned, no preservatives were added to the Eucharistic Host.

After all the evidence has been collected and examined, the head of the scientific team writes up a report. If the final conclusion is that what happened is scientifically inexplicable, everyone on the team has to assent. 

Following the scientific investigation, the local bishop convenes a theological commission to ensure nothing in play contradicts Church doctrine, before reaching a final judgment about the alleged miracle’s authenticity.

“Ultimately, it is the bishop who must make a decision,” Bishop Bonnici said. “Sometimes, the Vatican is consulted, but the final decision is with the bishop.” 


Assessing the Evidence

Three of the best-known, Church-approved Eucharistic miracles that have occurred were in Lanciano, Italy, in 750; Buenos Aires in 1992, 1994 and 1996; and Sokolka, Poland, in 2008. In all three of these renowned cases, modern scientific testing indicated that the Hosts involved have been transformed into human tissue.

But one of the problems with investigating Eucharistic miracles is that there is not an internationally recognized procedure for how to carry out the scientific part of the investigation. 

“The Lanciano Eucharistic miracle was thoroughly investigated in the 1970s by Dr. Edoardo Linoli. He was an Italian doctor and professor of anatomy and chemistry. He asked for samples and documented all his tests. The results were actually published in a scientific journal,” Stacy Trasancos, a Catholic author and speaker on issues of religion and science who has a doctorate in chemistry, told the Register. “He ran controls and explained his methods with the rigor expected of scientists.”

Other Eucharistic miracles have had samples sent to laboratories and analyzed, but only Lanciano’s investigation reached the rigor of getting accepted into a scientific journal.

According to Father Spitzer, when a Host appears to have been physically transformed into actual human tissue, the scientific team should include an electron screening specialist or a computer imaging analyst as well as the assessment of a histologist, a pathologist and a DNA expert. Microbiological analysis should also be undertaken.

“If you standardized a procedure [for scientific investigations] across the world, it would be great,” he said. “The problem is — and this is the same problem for certifying saints’ miracles — that it is the diocese where the miracle took place that convenes the scientific panel for analysis.”

Dioceses in different parts of the world do not follow a uniform way of scientifically investigating miracles, explained Father Spitzer, who has spoken about such miracles with the Register before.

Both Trasancos and Father Spitzer agreed that this situation could be remedied if the Vatican decided to specify the standard analytical procedures that should be undertaken when investigating alleged Eucharistic miracles.

“Maybe the Pontifical Academy of Sciences, for example, could publish a set of best practices for scientific investigations, which people can access,” suggested Trasancos.

Another problem with regards to these types of investigations is that bishops are not scientists.

“Whenever there is a miracle, people put pressure on bishops. Some people try to take advantage of them for an agenda,” said Trasancos.


Aids to Faith

Catholics are not required to believe in specific Eucharistic miracles.

“This is not because we doubt that God could work such miracles, but it is because we can never be certain of the scientific investigation,” stated Trasancos in her book, co-written with Father George Elliott, Behold, It Is I: Scripture, Tradition, and Science on the Real Presence. “… The Church urges prudence in the determination of modern supernatural phenomena.” 

Still, Catholics do believe that, at every Mass, the substance of the Host is mysteriously transformed into the Body of Jesus Christ. And Eucharistic miracles can serve to remind the faithful that this belief is really true.

“When things like this happen, it is to nurture and build up our faith. It is a wonderful gift,” said Bishop Bonnici. “What a wonderful way to encourage Eucharistic revival.”