Fish Eaters: The Whys and Hows of Traditional Catholicism

``Where the Bishop is, there let the multitude of believers be;
even as where Jesus is, there is the Catholic Church'' Ignatius of Antioch, 1st c. A.D

Our Lady of Guadalupe
and the Tilma of St. Juan Diego


Mexico of the early 16th century was still a land ruled by the Aztecs, a people whose demonic religion involved human sacrifice. Scholars estimate that between 20,000 to 250,000 people per year were sacrificed to the Aztecs' gods, and in one particularly bloody event -- the reconsecration of the Great Pyramid of Tenochtitlan in 1487, just five years before Columbus landed in the Americas -- 80,400 people were sacrificed over a period of four days. These human sacrifices would be taken to the top of the temple and laid down on a stone altar by four priests, one of whom would then use a flint knife to stab into the victim's belly, aiming his knife upward through the diaphragm in order to rip out his victim's still-beating heart. As the heart was placed into a bowl, the rest of the body was thrown down the temple stairs, at the bottom of which crowds gathered to dance and sing.

The victim would be decapitated, and the head de-fleshed, reduced to a skull. Then, two large holes would be bored into the skull, one on either side, and it would be slid onto a pole, forming the Emperor's tzompantli, which rather resembled a gigantic abacus with the beads replaced by victims' heads.

This is the world the Spanish conquistadors found when they crossed the Atlantic. And, thankfully, it is the world that Hernan Cortes conquered between 1519 and 1521.

Ten years after Cortes's conquest, on December 9, 1531, a peasant named Cuauhtlatoatzin -- now known as St. Juan Diego -- had a vision of Our Lady on a hill called Tepeyac in what is now Mexico City, a hill where the Aztecs once worshipped Tonantzin, their mother godess. She spoke to Juan in his native Nahuatl language, revealing to him that she is the Mother of the God, and that she wanted a church built on the hill.

Juan ran to tell the Archbishop, Fray Juan de Zumárraga, what he saw, but the Archbishop disbelieved him. On that same day, Juan saw Our Lady again, and she insisted he persevere, so on the following day, the 10th of December, he returned to the Archbishop and pleaded with him once more. This time, the Archbishop told Juan to ask her for a sign, some proof. So Juan returned to the hill and told the Blessed Virgin what
Zumárraga said. The Virgin told him that she would provide such a sign the next day. But by the time that next day came, Juan's Uncle had fallen dangerously ill, so Juan went off to find a priest for him. Ashamed at not having gone back to the hill, he went a different route, not wanting to confont Our Lady. Our Lady, however, met him on that divergent route he took, and chided him for not returning to her, asking him, "¿No estoy yo aquí que soy tu madre?" ("Am I not here, I who am your mother?"). She then told him that his Uncle had been cured, and that he should go to the hill and gather the flowers he'd find there. This he did. He gathered up Castilian roses, a flower that wasn't native to the area and that shouldn't have been found blooming in December even if they should've been growing there in the first place. Our Lady arranged the flowers in Juan's "tilma" -- the cloak he'd been wearing -- and then he ran with it to the Archbishop. Upon meeting Zumárraga, he opened up his tilma to reveal the miraculous roses. As he did so, something else was revealed as well: as the roses fell out onto the floor, the men saw that, on the tilma, a miraculous image appeared. It is that image that is the subject of this page.

After meeting with the Archbishop, Juan went to see his Uncle, who told him that he, too, had seen the Virgin. She had come to him as he lay sick, and she told him the story of her meeting with Juan, and also that she wanted to be known as Our Lady of Guadalupe, a title under which she'd been known in Castile, Spain since the 14th century. It is under that title that she's become the great patroness of the peoples of the Americas.

[You can read the original account of St. Juan's story, first written down in the Nahuatl language ca.1556, and translated to English in this document: Nican Mopohua (pdf)]

The Original Image and Additions To It

The image left on Juan Diego's tilma is a beautiful one, depicting a young woman with delicate features, olive skin, and long, straight dark hair parted in the middle, standing in an attitude of prayer, with hands together, and eyes cast downward. She wears a pink robe, with a Cross-shaped brooch at her neck. The robe is festooned with vines, flowers, and a quatrefoil motif, and underneath it, as you can see at her wrists, she is wearing a white undergarment. Over the robe, she wears a cerulean blue mantle. Around her waist hangs a belt, which is said to signify pregnancy, with two black tassles.

Later additions to the image include the the stars that adorn her robe, the gold leaf mandorla-shaped sunburst around her, the crescent moon upon which she stands, and the cherub holding up the moon.  At one point, the Virgin wore a 12-point crown, which was added in 1631 by Father P. Miguel Sanchez. It was removed in the late 19th century due to flaking of the medium used to form it. Many of these later additions were added by Fr. Sanchez to make the point that the Virgin depicted on the tilma is the woman written about by St. John in his Apocalypse.

At the top right side of the tilma, not affecting the image itself, is a stain made when nitric acid was accidentally spilled onto the tilma when the frame holding it was being cleaned. 

Science and the Image

Sadly, there is a lot of nonsense believed and spread about the image of Our Lady of Guadalupe. Some claim that the image isn't "on" the tilma, but floats above it a few micrometers away from the surface. Some claim that the image of the Virgin has a constant temperature of 98.6o, the average temperature of a living human being. Some even claim that a heartbeat can be heard when a stethoscope is placed over the image's abdomen. And so it goes.

While they are lovely thoughts, and I'm sure that those who present unverified assertions have nothing but good intentions and believe what they are reporting, those who repeat such claims are doing a great disservice to the Truth. We simply must be dedicated to Truth above all! God is in no need whatsoever of untruths, and Catholics have nothing -- not one single thing -- to fear from sound science. A too-credulous approach to the image of Our Lady of Guadalupe or to any other purported miracle only serves to make a mockery out of Catholics, leaving them wide open to accusations of naiveté. If you talk to an atheist and present misinformation that is easily disproved, why would he take you seriously when you present the Truths of the Faith? Faith and (sound) science can never conflict, so fear not, and always speak the Truth!

That said, the image is scientifically fascinating enough as it truly is.
Feeling like cottony silk to the touch, but looking coarse and rough to the eyes, the tilma is made of ixtle ("tampico"), from fibers of a plant known in Linnaean taxonomy as Agave popotule; it shouldn't have lasted more than a few decades. In fact, in 1787 Dr. Jose Ignacio Bartolache made two copies of the tilma and put them in two separate buildings in what is now Mexico City; both disintegrated by the end of a decade.

It was studied in 1979 by a biophysicist, USDA entomologist, and NASA consultant named
Philip S. Callahan, who wrote that the tilma and its image are inexplicable. After centuries, the fibers making the tilma itself show no deterioration, and there is no flaking of the original image's pigments. He wrote,

1. The original figure including the rose robe, blue mantle, hands and face, is inexplicable. In terms of this infrared study, there is no way to explain either the kind of color pigments utilized, or the maintenance of color luminosity and brightness of pigments over the centuries. Furthermore, when consideration is given to the fact that there is no under-drawing, sizing, or over-varnish, and that the weave of the fabric is itself utilized to give the portrait depth, no explanation of the portrait is possible by infrared techniques. It is remarkable that in over four centuries there is no fading or cracking of the original figure on any portion of the agave tilma, which - being unsized - should have deteriorated centuries ago.

2. Some time after the original image was formed, the moon and tassel were added by human hands, perhaps for some symbolic reason since the moon was important to both Moorish-Spanish and Aztec mythology.

3. Some time after the tassel and moon were added, the gold and black line decorations, angel, Aztec fold of the robe, sunburst, stars and background were painted, probably during the 17th century. The additions were by human hands and impart a Spanish Gothic motif to the painting. In all probability, at that time the tilrna was mounted on a solid support, and the orange coloring of the sunburst and white fresco added to the background. The entire tilrna for the first time was completely covered with paint. It seems unlikely that Juan Diego could have worn a tilma, stiffened with fresco on the fabric, to the Bishop's palace. Therefore, the original must have been the simple figure on the cloth

4. It is known that during the great flood of 1629, the Holy Portrait was taken from the Hermitage Chapel by canoe to the cathedral in Mexico City and that His Excellency Archbishop Don Francisco de Manzoyzuniga promised not to return the Virgin to the Hermitage until he could take her back with "dry feet" (Demarest and Taylor, 1956). It is my opinion that at this time, between 1629 and 1634 (when the image was returned to the Hermitage), the tilrna was folded at two different times into three sections causing the double fold creases across the lower and upper third of the body.

5. The pigments, utilized for the additions, can probably be easily identified, and indeed I have myself speculated as to what they may be. There is no way to identify any of the original pigments without obtaining samples of the colors for a modern chemical analysis and even then it may be impossible to identify them.

The pigments used in additions to the original image show flaking and peeling, but the original image is perfectly intact. Dr. Callahan wrote, too, that there is no brushwork on the image.

Many different opthamologists -- including Drs. Jose Aste Tonsmann, Manuel Torroella, Enrique Graue, Rafael Torrija, and Jorge Antonio Escalante -- claim that the Virgin's eyes exhibit what's known as "the Purkinje Effect" -- that is, they act as living human eyes in that they reflect objects four times, from the anterior and posterior surfaces of the corneas, and from the anterior and posterior surfaces of the lenses. The images they are said to reflect are believed to be what the image would've "witnessed" as St. Juan Diego unfurled his tilma in front of the Archbishop on that day in December of 1531: Archbishop Zumárraga and St. Juan Diego themselves (some claim that the figures of others are also visible, including those of a family).

Click to enlarge

For centuries, this beautiful and wondrous image has inspired the people of the Americas to love Christ and His Mother. Its History hasn't been easy, however. Though it should've fallen apart after a few years, for over twelve decades, it was radically unprotected, exposed to fluctuations of temperature and humidity, smoke and soot from the burning of candles and incense, the caresses of thousands of hands, touches from thousands of Rosaries, light, and breath -- but the icon remained intact. In 1795, a solution of nitric acid was spilled on it, but the icon remained intact. On November 14, 1921, an anticlericalist feigned being a man of faith who merely wanted to place flowers underneath the tilma to honor Our Lady. Instead of flowers, though, he placed a bomb made of dynamite. Its detonation could be heard over a half a mile away, and it horribly damaged the surrounding area -- but the icon remained intact.

The tilma can be seen at the Basilica of Our Lady of Guadalupe in Mexico City, where there's been a shrine to the Virgin since 1531, and which is
now one of the world's greatest sites of Catholic pilgrimage. The words spoken by Our Lady to St. Juan Diego -- “¿No estoy yo aquí que soy tu madre? ("Am I not here, I who am your mother?") -- are inscribed over the door of the basilica that is now built there. When you are in trouble, take those words to heart. She is here, and she is our mother.


Pete Baklinski, writing for, described something interesting about the image on the tilma: if you were to cover up the right side of the image, Mary appears to be smiling; if you cover up the left side, she appears to be sad. He relates this to two aspects of her message to Juan -- first, the reassuring message that she is his mother, she is there, and there is nothing to fear, and second, that she wants a chapel built so those who weep and sorrow will come and ask for her help.

Smiling Mary who reassures us

Sad Mary who grieves with us


The Virgin as Our Lady of Guadalupe is the patroness of the Americas and of the unborn. The feast day of Our Lady of Guadalupe is on December 12. Juan Diego was beatified in 1990 and canonized in 2002. He is remembered on December 9.


1 To get a sense of the hellish world the Spanish encountered, see Mel Gibson's visually stunning and exciting Apocalypto (2006).

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