Blood is seldom considered a pleasant topic, especially by the squeamish. But as Catholics we have to think about it and speak about it from time to time because it is so central to our faith.  We believe, after all, that our salvation was won for us by blood—and not just the blood that flowed through a human body in Palestine two thousand years ago, but the blood that was torn from that body and spilled upon the ground.

In the Creed we confess that Christ was “true God and true man,” which means that He had a truly human body with truly human blood coursing through His veins.

We call the Blood of Christ the Precious Blood because it is more valuable (precious) than all the accumulated riches of the world. In his famous Eucharistic hymn, Adoro Te Devote, St. Thomas Aquinas wrote that even “one drop” of His Blood has the spiritual power to save the entire human race.

That’s pretty astonishing.

So it’s no surprise that Catholics have always had an interest in certain religious artifacts that have shown evidence of or even actual stains of the Blood that was poured out for us on Calvary.

horizontal image of man on Shroud of Turin

The Shroud of Turin

Relics of Great Reverence

I’m speaking here not only of the famed Shroud of Turin but of other related historical artifacts, which Dr. Carlo Serafini calls the Passion Cloths in his fascinating book, A Cardiologist Examines Jesus (Sophia, 2021).

As relics, these cloths are witnesses to Christ’s life and death, but they are not scientific proofs that take away our need for actual faith in the Person of Christ Himself. Yet, science can certainly help us understand them.

Dr. Serafini’s study includes the Holy Tunic of Argenteuil (housed in the abbey of Saint-Denis near Paris) that has been venerated since antiquity as Christ’s “seamless garment” (John 19:23), as well as the Sudarium of Oviedo (in the Cathedral of Oviedo in Northern Spain) that is considered to be the neatly-folded face cloth found in the tomb on the morning of the Resurrection (John 20:7).

Assuming all three Passion Cloths are what we believe them to be, they would have absorbed some amount of the Precious Blood either after the scourging (Tunic) or at the burial following the Crucifixion (Shroud and Sudarium).

Most fascinating of all is that a number of the blood stains on the Tunic and the Sudarium correspond exactly to several of the prominent blood stains on the Shroud.

Various teams of scientists from many different specialties and nations examined the Passion Cloths throughout the 20th century, and in his book, Dr. Serafini carefully analyzed all the data about the blood contained on them. In each case, scientists came to the same conclusion that the blood on these ancient cloths is actual human blood, not blood from an animal or stains created by any other substance.

This conclusion does not prove that the blood is Christ’s Blood, of course, but it sets the foundation for other conclusions that I’ll describe below. And the Passion Cloths are not the only witnesses to Christ’s Blood in the Church’s history.

Tunic of Argenteuil on display in Paris
Ancient cloth of Christ in Oviedo

The Holy Tunic of Argenteuil

The Sudarium of Oviedo

Eucharistic Miracles

Dr. Serafini also examined numerous scientific studies done on five Eucharistic miracles, which purport to contain congealed blood and tissue that appeared miraculously in consecrated hosts. All studies carried out were done with modern scientific instruments and methods.

One of the miracles studied (Lanciano, Italy) dates back to 700-750 AD and still contains enough material to be examined scientifically today. The other four Jesus Sacred Heart surrounded by angels and goldmiracles are from the 20th century (from Mexico, Argentina, and Poland).

First of all, the studies indicated clearly that four of the five samples (the ancient Lanciano sample included) contain human blood.

But that is not the most incredible result. Scientists also determined that each of the five consecrated hosts contains identifiable human tissue side by side with the substance of the host. Further analysis proved that the tissue in each case comes from the heart muscle of a man.

Let the full impact of these conclusions sink in:

  • The ancient Passion Cloths contain human blood.
  • The Eucharistic miracles contain both human tissue and human blood.
  • The tissue is of one type only: male heart muscle tissue.

The most astonishing conclusion of all, however, is that the human blood evident in all of these artifacts is of a single blood type – AB.

Human Blood, Divine Messages

The studies are extremely complex, so I’m only going to zero in on the issue of the blood type. The presence of human blood on these artifacts allows scientists to identify the blood type with scientific precision. Blood typing was done on the three cloths and two of the five Eucharistic miracles.

So, let’s focus on a few fascinating facts about this blood type and its occurrences in these artifacts.

1.     AB is the rarest type of human blood in the world.

Scientists estimate that the AB blood type is shared by as little as four percent of the entire human population. AB-Positive represents 3.4%, and AB-Negative comprises only 0.6% of all human blood types.

Dr. Serafini believes these samples were all AB-Negative, which would put Christ’s Blood in the category of the rarest of all blood types. Serafini doesn’t hesitate to call it royal: “If there were an aristocratic blood group, in a way, the AB group would be it. AB is well-suited to the most precious and royal blood type in the history of humanity.” (199)

2.     The mystery of the Virgin Mary’s blood type.

The blood type of a child comes from the parents, of course, but what happens when a child is born without a biological father? There are two possible answers to this question, both of which are biologically inexplicable.

The first is that Our Lady’s blood type was also AB and that she passed it on to Jesus without the contribution of a human father. Here we face a biological anomaly: passing on genetic material directly without a biological partner would result in a clone, an identical copy of the single parent. But Jesus was male, so He was definitely not a clone of His mother!

The second is that in most cases of AB children, one parent contributes the A and the other contributes the B. But such a scenario would be equally impossible for Jesus, whether the Blessed Mother contributed the A or the B: there was no biological father to contribute the corresponding type.

In short, whether Mary’s blood was A, B, or AB, Jesus’ AB blood represents an immense mystery that can only be solved by belief in some kind of divine contribution of the male element, as in Luke 1:34-37:

But Mary said to the angel, “How can this be, since I have no relations with a man?” And the angel said to her in reply, “The holy Spirit will come upon you, and the power of the Most High will overshadow you. Therefore the child to be born will be called holy, the Son of God…for nothing will be impossible for God.”

3.     Jesus’ blood type itself is indicative of His mission.

Many mistake the AB blood type for the universal donor and believe that it is fitting to the God-Man who shed His Blood as a universal sacrifice for the human race. This is a pious belief but both scientifically and spiritually unsound. (The universal donor blood type is O.)

Medically, the AB blood type is the universal receiver; it can take into itself any other type of human blood. There is an important theological message here. Dr. Serafini calls this type of blood the “universal solvent.” That is, it can mix with and dissolve all other types of human blood into itself.

This is an astounding conclusion that fits perfectly with the saving mission of the Redeemer of mankind. In as much as blood signifies human suffering, each and every human being that has ever lived or ever will live can join his sacrifices to the saving Blood of Christ to participate with Christ in the ongoing redemption of the world.

4.     It makes Eucharistic miracles almost impossible to fake.

Referring back to the relics and miracles, the rarity of the AB blood type (only identified in 1907!) undoubtedly would make Eucharistic hoaxes extremely unlikely. How is it possible that the blood of an 8th century Eucharistic miracle in Italy would track scientifically and perfectly with a 1st century Palestinian crucifixion cloth like the Shroud or the 20th century miraculous events in Poland, Argentina, Mexico (and other places we have not even mentioned)? This leads us to our final point.

5.     The numbers don’t lie.

Dr. Serafini’s studies determined that the rarity of the blood and its recurrence through time in these artifacts establishes a high degree of certitude about their authenticity as witnesses to the Crucifixion.

Three occurrences of AB blood on such diverse relics is one in 8,000. That’s rare enough. Four occurrences of AB blood in such different relics goes up to one in 160,000. Then, the chances of five occurrences (as in his studies) swells to one in 3.2 million.

He thus says that we are dealing with a 99.99% degree of certitude that the blood of these ancient and modern artifacts is authentic – and probably from the same man.

I don’t know about you, but these days…I follow the science.


[Note: This article is a reproduction of the Sacred Windows Email Newsletter of 5/15/22, so it does not end with the regular Soul Work section. Please visit our Newsletter Archives.]

Photo Credits: Holy relics via Wikimedia Commons. Feature image by Crystal Blair and stained glass by Paul Wellauer via Pixabay