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The Christian Code

My parish church arose during the Catholic building boom of the early 20th century: a Gothic monument in concrete block, stone, and stained glass. These materials were then in abundant supply, as were immigrant laborers, many of them Catholic, many of them willing to volunteer a daily shift after they had worked their night shift in the steel mills.

Literacy was still a luxury, so there are few texts on the walls or windows of old St. Agatha’s. Faithful to the traditions of the Church and their craft, Christian artisans relied on the power of symbols to teach and confirm the faith. And so these simple and mysterious images crowd the windows: a fish, a lamb, a lamp, a dove, a crown, a sword, a burst of flames, a ship, a vine, a hand, a loaf of bread. The designers and builders—and, of course, the pastors—lavished attention on these small details. Why? Because they knew that a single small symbolic image could evoke a warehouse full of meaning; a single symbol could trigger the accumulated devotion of many generations.

The fish, the lamb, the lamp, the loaves—these are the images the immigrants knew from their childhood in the old country. Their ancestors knew them, too, from churches and ruins and even bridges and public buildings. Most of these symbols recur throughout the Christian centuries, going back to the earliest churches and cemeteries and the most common items of everyday life.

Catholic: All Times and Peoples

Some years back I wrote a book about early Christianity called The Fathers of the Church: An Introduction to the First Christian Teachers. Again and again I recognized in ancient Christian texts the rites and doctrines of the Catholic Church today. The oldest texts—the Didache, St. Clement of Rome To the Corinthians—take us back to the lifetime of the apostles. Others were written shortly afterward: the seven letters of St. Ignatius of Antioch, the letter of St. Polycarp To the Philippians, and the eyewitness account of Polycarp’s martyrdom. In those documents we encounter the churches established by the apostles—in Rome and Corinth, Antioch and Ephesus and Smyrna—and we learn that those churches were hierarchical and liturgical, centered on the Eucharist, and already concerned with the proper transmission of Tradition and exercise of authority. They delight in the identity they share as they speak of the “Catholic Church”—a body that is united, though it was multicultural and worldwide.

I found it fascinating that these ancient preachers and correspondents, though from different lands, drew from a common store of rhetorical devices, metaphors, and symbolic allusions. Writing from Rome to Corinth, for example, St. Clement could invoke the story of the phoenix—the mythological bird that dies in flame and rises from the ashes—as an obvious sign of the Resurrection. St. Ignatius of Antioch could compare his own impending martyrdom to a ritual sacrifice of wine and bread. A few years on, Hermas could speak of the Church using the figure of a lighthouse. For Tertullian of North Africa and St. Hippolytus of Rome, the Church was a ship. For St. Justin Martyr and later St. Irenaeus, Christ was a plow, his divine and human natures coming together like wood and metal to prepare the whole earth for a rich harvest.

Again, I became fascinated by the Fathers’ common language because it is the symbolic language I could “read” on the stained-glass windows of my 20th-century parish church! Though their world was distant from my own and foreign in so many ways, their Church was clearly my Church. It was catholic, that is, universal, not only in space, but also in time. Pope St. Clement could speak eloquently and authoritatively not only to his contemporaries in faraway Greece, but also to his spiritual descendants in the little town of Bridgeville, Pennsylvania.

The research for my later books on the Fathers—The Mass of the Early Christians, The Way of the Fathers, and Living the Mysteries (co-authored with Scott Hahn)—only deepened my interest. When I saw those symbols in my parish church, I saw them illumined by flashes of light from the preaching of the ancients.

Then came the bomb (so to speak). I made my first trip to Rome, where I trod the same roads as the Fathers, prayed in their churches, and walked the corridors of their catacombs. What before had been mere flashes of light now seemed like brilliant explosions. And the symbols were everywhere—carefully carved or etched crudely as graffiti. There was St. Clement’s phoenix, rising up in an ancient mosaic. There, again and again, was the fish. There was the lamb, the ship, and the anchor. In museums they appeared on signet rings and on the surface of lamps, on liturgical vessels (such as chalices and pyxes) and on burial caskets.

The experience was overwhelming. I made up my mind to write a book about the use of symbols in the writings of the Fathers and early Christian art. That book took shape, eventually, as Signs and Mysteries: Revealing Ancient Christian Symbols, which was abundantly and beautifully illustrated by the Czech artist Lea Marie Ravotti.

Archaeological Apologetics

The Church’s re-appropriation of many ancient symbols came with the accidental rediscovery of the Roman catacombs in 1578. Faithful Catholics saw the event as providential. Much of Europe had fallen under the spell of Protestant doctrine, with its radical reinterpretation of early Christian history. Yet the first reports from the catacombs told of chambers that looked and felt like Catholic churches. First of all, there were sacred images on the walls. There was abundant evidence of devotion to the saints. There were references as well to an established Church hierarchy of pope, bishops, priests, and deacons. There were small items that we would call sacramentals, such as medals and reliquaries. And throughout the halls and cubicles, eucharistic imagery dominated the frescoes and inscriptions—banquet scenes with bread and wine, for example, and sheaves of wheat paired with clusters of grapes.

Catholic apologists delighted in these findings. The catacombs seemed to confirm the continuity of Reformation-era Catholicism with the earliest Christian faith. No doubt, some members of the “Roman School” let their enthusiasm carry away their interpretations. But they were certainly no more ideologically motivated than their opponents.

And their opponents were indeed vehement. Critics charged that the Roman School treated the science of archaeology as if it were simply the handmaid of apologetics. But the burden fell, then, upon the critics to explain (or explain away) the evidence found in the catacombs.

They did this, and they continue to do this, in rather ingenious ways. One way is to demand that art and documents must be interpreted in isolation of one another. A more recent development, no doubt inspired by Karl Marx, sees the two bodies of ancient remains—art and text—as emerging from two entirely different social classes: the painting proles and the wealthy wordsmiths. According to this theory, even though the sermons and inscriptions, the lamps and the letters, employed the same symbols, they probably used them to communicate totally different messages. (This, like most Marxist theories, flies in the face of not only lived reality, but also the historical record, which retains no evidence whatsoever of class struggle in the early Church. What’s more, the catacombs’ more elaborate artwork—while it would certainly have appealed to the illiterate poor—could only have emerged with the subsidy of wealthy Christians.)

The Roman School did have its zealots who let their enthusiasm drive their interpretation. The 19th-century convert from Anglicanism William Palmer produced a book, An Introduction to Early Christian Symbolism, that transgressed many of the rules—for example, combining elements of paintings found in one chamber with those of artworks found elsewhere. But these were the exceptions rather than the rule.

Today, as the universities grow more secularized, the old Protestant-Catholic apologetic battles have faded from the foreground, and this has actually been good for the claims of the old Roman School. Art historians like Robin Margaret Jensen of Vanderbilt have successfully re-integrated the study of art and texts, treating them as two complementary “modes of communication.” She explains: “[V]isual images provide an extraordinary testimony to aspects of the hopes, values, and deeply held convictions of the early Christian community” (Understanding Early Christian Art, 30-31).

And in much of Dr. Jensen’s work, modern Catholics can recognize those “hopes, values, and deeply held convictions” across the millennia as our own. Our hope is an anchor (Heb 6:19-20). The conviction we cling to is a fish.

Christians to Come: Heed Well!

What, then, is the apologetic value of ancient Christian symbols? What is their explanatory power?

They are not simply illustrations of the homilies of the Fathers. Rather, both the texts and the images are expressions of a distinct Christian culture, tradition, and experience. Both are reflections upon the gospel. Both proclaim the gospel, though in different ways. Each is helpful in the interpretation of the other. Both confirm the place we share with the ancients in the Church—militant and triumphant—the communion of saints that is so vast as to be universal: that is, catholic.

To learn the symbols as they appear in the Fathers and in the ruins is to go deep in history, and, as Cardinal Newman said, to be deep in history is to cease to be a Protestant.

While the ancient symbols can’t serve as proof texts, and they don’t carry the same explanatory power as theological treatises, they do have their own mysterious ways of persuasion. They are urgent messages sent from long ago, and we, the Christians of their future, are the intended recipients. Woe to us if we do not heed the gospel they took such care and such trouble to proclaim.

I have dedicated a book to the “reading” of many ancient symbols. Here I have space to treat just a representative sample. For their apologetic value, let us consider the fish and the symbolic representation of Moses striking the rock.

ICHTHYS: Ancients’ Mnemonic

The fish is the symbol most commonly associated with the ancient Church. It is everywhere in the archaeological record—scratched onto walls as graffiti, traced onto lamps, and detailed in beautiful mosaics and frescoes. The Fathers left an impressive paper trail explicating the fish and its many layers of meaning, for the symbol was as complex as it was common. The only symbol comparable, for modern believers, is the cross.

What did the fish represent? Above all, it was Jesus Christ. The dominant language of the early Church was Greek, and in Greek the phrase “Jesus Christ, Son of God, Savior” produced the acronym ICHTHYS, the Greek word for fish. A Christian poem of the second century spells the word with the first letters of each line. Thus, the fish is a simple creed: It professes belief in Jesus’ divinity and his identity as the Christ, the anointed Savior (see Mt 16:16).

Scholars, however, believe that the visual symbol preceded the acronym. Fish are plentiful in the Scriptures that were proclaimed in the Church’s liturgy, so the symbol evoked many scenes familiar from sacred history. Ezekiel prophesied, “And wherever the river goes . . . there will be very many fish . . . Fishermen will stand beside the sea . . . its fish will be of very many kinds, like the fish of the Great Sea” (Ez 47:9-10), and his oracle was often interpreted as a vision of the future Church, whose baptismal “river” would be home to many “fish”—that is, many Christians who are identified with Jesus Christ. The fishermen who “stand beside the sea” foreshadow the apostles and their successors, the bishops, whom Jesus appointed as “fishers of men” (Mt 4:19).

The fish is Jesus, and the fish is also the individual believer. There is no contradiction here and no confusion. Writing in North Africa around A.D. 198, the Christian theologian Tertullian explained: “We little fishes, after the example of our fish, Jesus Christ, are born in water. Nor have we safety in any other way than by permanently abiding in water” (On Baptism, 1). Though he writes in Latin, Tertullian shifts to the Greek word ichthys when he describes Jesus. Surely he means his hearers to remember the acrostic “Jesus Christ, Son of God, Savior,” which was by then firmly established in Christian culture.

Indeed, such fish symbolism may originate in the common patrimony of Christians and Jews. The prophet Habbakuk had said, “You have made man like the fish of the sea” (Hb 1:14); and, according to the Babylonian Talmud, Rabbi Samuel offered an interpretation strikingly similar to that of Tertullian, his Christian contemporary. “Men are compared with fishes,” said the Jewish sage, “because just as fishes of the sea die at once when they come up on dry land, so does man also die as soon as he abandons the Torah and the precepts” (Babylonian Talmud, Abodah Zarah, 3b).

A Christian separated from the Church, like a Jew apart from the Torah, is a creature out of his element—a fish out of water—condemned to spiritual death.

The Fish of Life

But we have not yet touched on the original and the deepest meaning of the fish. The fish is the primal symbol of the Holy Eucharist. One need not be Catholic to recognize this fact. Erwin Goodenough, an agnostic scholar at Yale University, wrote that the Gospel according to John—which he called “the primitive Gospel”—gives us “the earliest explicit acceptance of the fish as a eucharistic symbol and as a symbol of the Savior who was eaten in the Eucharist” (Jewish Symbols in the Greco-Roman Period: Fish, Bread, and Wine, 33). John does this, in his sixth chapter, by moving immediately from Jesus’ multiplication of the loaves and fishes to the Bread of Life discourse, our Lord’s most famous eucharistic sermon. At the end of John’s Gospel, we see the figures of fish and bread return as Jesus prepares a lakeside meal for the disciples (Jn 21:9). For the early Christians, all of these events prefigured the life-giving blessing that Jesus bestowed upon the Church. The Protestant archaeologist Graydon Snyder concluded: “[T]he fish was, with the bread, the primary symbol for the Eucharist, the meal that developed, maintained, and celebrated the new community of faith” (“The Interaction of Jews with Non-Jews in Rome” in Judaism and Christianity in First-Century Rome).

No text could make the association as clearly as one particular depiction in Rome’s Catacomb of St. Callistus. There we see two fish on a gravestone, one fish bearing bread, the other bearing a cluster of grapes: the eucharistic bread, the eucharistic wine—and the symbolic eucharistic fish.

Two famous tombstones speak of the fish in eucharistic terms. The first bears a 22-line poem dictated by a bishop named Abercius, from Hieropolis in Phrygia (now part of Turkey), around A.D. 216. The poem is as allusive and symbolic as the paintings of the catacombs—encoded so that only a Christian could understand: “Faith was my guide, and set before me as nourishment the fish from the deep. Very large, very pure, this fish that the chaste virgin held in her arms; that she gave to its friends to eat everywhere, having excellent wine, giving it as a drink mixed with water, together with bread.”

The second inscription is later and was excavated in Autun, France. Its age is uncertain, but its style corresponds to that of Abercius, using similarly cryptic language to describe the Eucharist. The gravestone exhorts the living to make the most of their Mass—to eat, drink, and be merry, in the most spiritual sense: “O divine race of the heavenly fish, with a respectful heart receive immortal life among mortals. Rejuvenate your soul, my friend, in divine waters, by wisdom’s eternal streams, which give true riches. Receive the delicious nourishment of the Savior of the saints. Eat, drink, taking the fish with both hands.”

There are many variations on the theme of the eucharistic fish. The fish appears often in wall paintings that depict banquet scenes. It is possible that these images present a snapshot of the agape meal, the dinner that sometimes accompanied the Eucharist in the primitive Church (see 1 Cor 11). Most likely, however, these fish are symbols of the Real Presence of Jesus Christ in the Eucharist, for even the Last Supper appears often as a fish dinner rather than a Passover meal. In fact, that is the way it appears in an ancient mosaic of the Last Supper, at Tabgha, near Capernaum—the very site in the Holy Land where Jesus multiplied the loaves and fishes.

The fish is a creed. It is baptismal. It is eucharistic. It is Christ. It is the Christian. By faith, by baptism, by the Eucharist, believers know communion with God. They are identified with him, partakers of the divine nature (2 Pt 1:4)—little fish in the likeness of the big fish, who is Jesus Christ.

Water from Petrus

In the most common depiction of Moses in ancient Christian art, he isn’t really Moses at all. He is a symbol of St. Peter, and that is made clear by annotation. The artists often provided a caption, painting the Latin word Petrus above the head of the Moses figure. In several images, Peter appears receiving the divine law from Jesus Christ, just as Moses received the tablets of the law from God.

Most often, however, Peter appears striking a rock with a stick, thereby releasing streams of water, just as Moses had done in the desert (Ex 17:6). There are well over a hundred surviving examples of this image from the ancient Roman world.

It is possible that the correspondence arose because of the similarity between the name Peter (Petros, Petrus) and the Greek and Latin words for “rock” (Petra). Hearing the Scriptures from First Corinthians or from Exodus, Christians could not help but make the association with the Prince of the Apostles.

When St. Paul discussed the incident in the desert (1 Cor 10:4), he spoke of it as a foreshadowing of baptism.

Thus, the pictures seem to say: As Moses released water for the refreshment of the Israelites, so Peter releases the waters of baptism for the redemption of all people. As Moses was a type of Jesus Christ, so he was also a type of Christ’s vicar on earth, the apostle Peter.

The images may also refer to an old tradition of Peter’s final days on earth. Before his execution, so the story goes, he was incarcerated in the city prison near the Roman Forum, assigned to the dreaded Tullianum, the stinking subterranean cell. Not one to waste an opportunity, he preached the gospel to his cellmates and jailers, eventually converting 47 men. The jailers begged for baptism, but there was no water in the cell. Peter took up a stick and struck the rock floor, causing a pure spring to bubble up from below. Today, if you visit the Mamertine Prison near the Roman Forum, you will see that a spring still flows from the floor.

We possess no written account of this incident before the late fourth century. It may be an oral tradition passed, like many others, from generation to generation of Roman Christians. It may also be an imaginative reading of the symbolic paintings of Moses as Peter.

Neither do we know for certain that Peter was imprisoned in the Tullianum. Some historians believe he was under house-arrest somewhere near the Forum. We do know that the Church of Rome—in the early fourth century and perhaps earlier—honored Peter’s two jailers, Processus and Martinianus, as martyrs.

Peter-as-Moses images have been found most abundantly in and around Rome—on sarcophagi, on gilded glass, and in murals—but not only in Rome. One was unearthed, for example, on a plate found in modern Montenegro. This last one bears the legend (in Latin): “Peter struck with his rod, and the founts began to run.”

The Moses imagery recurs as well in the Fathers’ discussions of the Prince of the Apostles. Aphrahat the Persian Sage makes the connection in the first half of the fourth century, as do St. Macarius of Egypt, St. Ephrem of Syria, St. Augustine of Hippo, and St. Maximus of Turin after him. From Moses to Christ to Peter—Aphrahat makes complete the chain of associations, and he uses a dialect of the Aramaic language used by Jesus himself: “Moses brought forth water from the rock (kepha) for his people, and Jesus sent Simon Peter (Kepha) to carry his doctrine among the peoples” (Aphrahat, Demonstrations 21.10).

The message of the images is clear. As God gave his authority on earth to Moses, and Moses in turn oversaw the life and worship of Israel, so the rites, the law, and the authority in the New Covenant have passed from Jesus Christ to Peter, and from Peter to his successors, the popes.

Unearth the Treasure

A symbol is, by definition, something that stands for or suggests something else. The relationship of the sign to the signified can be complex. And each Christian symbol has its own suggestive power, its own resonances, its own evocations of Scripture. Each symbol reflects a different aspect of some reality that many symbols hold in common. The Eucharist represented as mother’s milk (present in catacomb art as well as the doctrine of the Fathers) elicits a different response in the beholder than, say, the Eucharist as the Passover Lamb or the fish.

Erwin Goodenough, though an unbeliever, put the matter very well: “The symbols of Christianity . . . are indeed many . . . Yet all of these will fit into a single formula, namely that the eternal God lovingly offers to share his nature with man, to lift him into eternal participation in divine life and happiness. Each symbol presents a facet of a single jewel” (Jewish Symbols in the Greco-Roman Period, 56).

That jewel is, for us moderns, too often a treasure hidden in a field (see Mt 13:44). It is up to each of us to buy back these treasures of Christian antiquity, and not just the symbols themselves, but the things they stand for—the supernatural realities—in order to share them with the world.


In depicting their faith, early Christians drew heavily from the surrounding cultures—clearly illustrating a faith for all times, places, and people.

Images of Christian belief comprise animate and inanimate forms, mythical and actual creatures—even letters of the alphabet.

  • The Fish (see discussion pgs. 16-18)
  • The Orant – Typically a depiction of a woman with arms outstretched in prayer, an imitation of Christ’s dying posture.
  • The Shepherd – One of the most common representations of Jesus, based on the Lord’s own words (“I am the Good Shepherd”), as well as on Psalm 23.
  • The Vine – Inheriting deeply Jewish symbolism, Christians remembered Christ’s identification of himself as the vine. The vine also symbolizes the eucharistic wine.
  • The Philosopher – Christ (and Christianity) is represented as a wise man in a pallium or robe—a symbol of philosophical authority; Christianity was deemed superior to all competing philosophies.
  • The Phoenix – This mythical bird, believed by ancient peoples to burn up and rise anew from its ashes, was an early symbol of the Resurrection.
  • The Dolphin – A symbol of rescue, friendship, and guidance, this sea mammal was associated with Christ by early Christian sailors.
  • The Peacock – In addition to symbolizing God’s magnificent artistry, the peacock’s beautiful feathers, shed and then replenished, represented the risen Christ.
  • Milk – Explicit references from the Old Testament compare to God’s grace and providence to milk, an image later likened to eucharistic food and also producing the image of Mary as nursing Mother (Maria Lactans).
  • The Lamp – Both a symbol and a medium for other symbols, the lamp held a central place in the lives of ancient peoples, representing truth and providing sources of illumination for worship and pilgrimage.
  • Moses (see discussion pgs. 18-19)
  • The Plow – A symbol of God, who tills the soil of human hearts; of peacemakers; and of the cross.
  • Vessels – Perhaps representing what they contain, be it water, oil, the blood of martyrs, or wine for the Eucharist.
  • The Lamb – A twofold meaning: the lamb in the arms of the shepherd symbolized the believer, safe in Christ’s care; the lamb alone was Christ himself—the symbol of the New Covenant whose sacrifice “takes away the sins of the world.”
  • The Dove – Although later Christians associated the dove with the Holy Spirit, in ancient art the dove represented the believer’s soul, rising above earthly cares after death.
  • Bread and Sheaves – Bread, a common image, was a reminder of the multiplication of the loaves and fishes, but principally a symbol of Christ, the Bread of Life.
  • The Crown – A symbol of royalty since ancient times, it came to represent divine life in Christ—and especially martyrdom.
  • The Banquet – A complex and mysterious symbol, debated as either a realistic depiction of a Christian gathering or a more symbolic image alluding to biblical descriptions of the heavenly banquet.
  • The Lighthouse – The Christian faith, a beacon of hope in a tumultuous world.
  • The Ankh – A cross with a loop at the top, an ancient pagan Egyptian symbol of life after death, adopted by Coptic Christian communities as a version of Christ’s cross.
  • The Cross – The “pre-eminent symbol of the Christian faith” is almost nowhere to be found in early Christian art—or else commonplace but hidden. Perhaps one reason the first Christians chose not to use it is that they did not need to: Roman crucifixions were a constant reminder of the price of redemption.
  • The Anchor – Hope of salvation, almost always incorporating a cross.
  • Ships and boats – Recalling the ark of Noah, a symbol of the Church—safety amid the world’s tempests.
  • The Chi-Rho (Labarum) – Combining the first two letters of Christ in Greek, chi and rho, the labarum was a term denoting a military leader’s standard or rallying symbol; Constantine claimed to have received a vision of the labarum, and under it he led his forces to victory.
  • Alpha and Omega – From the book of Revelation, a reminder that God encompasses all times, places, and persons—a symbol of hope eternal.

—Source: Signs and Mysteries: Revealing Ancient Christian Symbols (Our Sunday Visitor)

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