The Christian Symbols of the Catacombs

The discipline of the secret

The art of the catacombs is deliberately allusive. The first Christians lived under a hostile state religion, and they kept the most intimate mysteries of the faith — baptism, the Eucharist, the exact content of the sacraments — away from uninitiated eyes. Historians call this reserve the disciplina arcani, the discipline of the secret.

The Catholic Encyclopedia sums up its effect on art as follows: monuments exposed to all eyes "could not speak of the mysteries of religion save under veiled symbols"^[1]. The fish, the anchor or the shepherd are therefore not spies' codes: they are signs of recognition among believers, yielding their full meaning to those who already share the faith, and remaining mute or innocuous to the outsider.

This discretion explains why the bare cross is almost absent from the catacombs, why the Passion is never shown head-on, and why so many images pass through the Old Testament. The faith is not hidden out of shame; it is protected, and expressed through figures.

A language of hope, not of fear

The choice of scenes obeys a remarkably unified logic: almost all of them tell of a deliverance. Jonah comes out of the sea monster, Daniel escapes the lions, the three young Hebrews pass through the furnace without burning, Noah survives the Flood, Lazarus comes out of the tomb. On a tomb, these images are not neutral biblical illustrations: they are a prayer for the deceased, a way of saying "as you saved this one, save him who rests here".

That is why the art of the catacombs almost entirely ignores ancient funerary pathos. No mourners, no despair, no gloomy afterlife. The deceased is often depicted as an orant, standing, arms raised, already at peace. Christian death is a birth, and the walls say so in colour.

Chronological markers

The oldest frescoes of the Roman catacombs go back to the late 2nd and early 3rd century, notably at Priscilla and Callixtus^[2]. Production continues throughout the 4th century, diversifying after the peace of the Church. The symbolic vocabulary itself is older still: the inscription of Abercius, engraved in Asia Minor as early as the second half of the 2nd century, already attests to the Eucharistic fish^[3].

ICHTHYS, the acrostic

The most distinctively Christian symbol of the catacombs is the fish. Its power comes from a play on words: in Greek, fish is ΙΧΘΥΣ (ichthys), and each of its five letters opens a word of a miniature confession of faith:

• Ι — Iēsoûs (Ἰησοῦς), Jesus
• Χ — Christós (Χριστός), Christ
• Θ — Theoû (Θεοῦ), of God
• Υ — Hyiós (Υἱός), the Son
• Σ — Sōtḗr (Σωτήρ), Saviour

"Jesus Christ, Son of God, Saviour": the whole Creed fits into a fish drawn in two strokes of the stylus. The sign is perfect for the discipline of the secret — commonplace for a Roman, luminous for a Christian^[8].

The fish and baptism

Tertullian gives the symbol its baptismal key. In the first chapter of his treatise On Baptism, he plays on the image of the fish that lives only in water:

"But we, little fishes, after the example of our ΙΧΘΥΣ Jesus Christ, are born in water, nor have we safety in any other way than by permanently abiding in water." — Tertullian, On Baptism, 1^[9]

The Christian is a pisciculus, a little fish born of baptismal waters, who survives only by remaining united to the great Fish, Christ. On a tomb, the fish therefore recalls the baptism that made the deceased a son of God — the sacrament by which he entered the life that no death takes back.

The inscription of Abercius

The oldest stone bearing this symbolism is not in the catacombs but sheds light on them. The epitaph of Abercius, bishop of Hierapolis in Phrygia, engraved towards the end of the 2nd century, describes in veiled images a journey of faith to Rome and a mysterious food:

"Everywhere faith led me forward, and everywhere supplied my food, the fish from the spring, mighty and stainless, whom a holy virgin seized, and gave this to friends to eat always, having excellent wine, giving it mingled with bread." — Inscription of Abercius^[10]

The "fish from the spring" is Christ; the "wine mingled with bread" is the Eucharist. The text shows that even before the great Roman frescoes, the fish was already linked to Christ and to the Eucharistic table. The painted imagery of the catacombs merely extends a symbolism that was already mature.

Before the Church dared to represent Christ in majesty, it painted him as a shepherd. The Good Shepherd — a beardless young man carrying a sheep on his shoulders — is the most frequent image of the catacombs. It is found on the ceilings of Priscilla and among the oldest frescoes of Callixtus^[11][12].

The image condenses two parables. It first tells of the lost sheep of the Gospel: the shepherd who leaves the ninety-nine to seek the hundredth and joyfully brings it back on his shoulders (Luke 15:4-5). It then tells of the Good Shepherd of St John, who lays down his life for his sheep:

"I am the good shepherd. The good shepherd giveth his life for his sheep." — Jesus, Gospel according to St John 10:11^[13]

On a tomb, the meaning is immediate: the deceased is the sheep found again, carried by Christ out of the danger of death. The motif echoes an intuition of all antiquity — the figure of the sheep-bearer existed in pagan art — but Christians baptized it and gave it an entirely new meaning: this shepherd saves eternally.

Beside the Shepherd, one silhouette recurs constantly: a standing figure, most often female, arms spread and raised, palms open towards heaven. This is the orant (or orans), man at prayer. This attitude, older than Christianity, was adopted by the Church as the very image of trusting prayer.

In the catacombs, the orant does not merely represent the liturgical gesture: it chiefly depicts the soul of the deceased, already saved, standing in the peace of God. It is, in the historians' phrase, "an abstract representation of the soul of the deceased", one of the most frequent motifs of funerary frescoes and graffiti from the 2nd century onwards^[14].

The orant thus carries the whole wager of the art of the catacombs: the dead are not shown lying down, but the soul living and praying. The tomb becomes the place of a prayer that continues, from the deceased towards God and from the Church towards the deceased.

The anchor is one of the signs most beloved by engravers of funerary slabs. Its meaning is given by the Epistle to the Hebrews, which compares Christian hope to an anchor cast into heaven:

"Which we have as an anchor of the soul, sure and firm." — Epistle to the Hebrews 6:19^[15]

On a tomb, the anchor says that the deceased held fast, moored to Christ beyond death. The anchor is often associated with the fish: there is the well-known representation, in the Catacomb of Priscilla, of a cruciform anchor from which hang two fishes — that is, Christ (the fish) fixed to the cross suggested by the anchor^[16]. The neighbouring inscriptions — in pace, pax tecum — confirm the atmosphere: peace, not anguish.

The anchor is also a good example of the symbolic prudence of the catacombs: its upper part already traces a cross, but in a form ordinary enough not to expose the most sacred sign to profanation.

The dove

The dove, often holding an olive branch in its beak, numbers among the gentlest paintings of the funerary chambers^[17]. It combines several meanings: the peace of the soul (through the branch, echoing Noah's dove), and the Holy Spirit descended upon Christ at the Jordan. On a tomb, it proclaims that the deceased has entered into rest.

The vine and the branches

The vine runs across the vaults, its branches laden with clusters, sometimes with harvesters^[18]. The image refers directly to the word of Christ:

"I am the vine; you the branches. He that abideth in me, and I in him, the same beareth much fruit." — Jesus, Gospel according to St John 15:5^[19]

The vine expresses living union with Christ; it also evokes Eucharistic wine. The deceased resting beneath a vault of vine is depicted as a branch that remains attached to the stock, even in death.

The broken bread

Several frescoes show guests around a table where bread is broken. The most famous, known as the Fractio Panis, is found in the "Greek Chapel" of the Catacomb of Priscilla (first half of the 3rd century); De Rossi, according to the Catholic Encyclopedia (art. "Fractio Panis"), hailed it as "the pearl of Catacomb discoveries"^[20]. Tradition recognises in it a Eucharistic scene.

A nuance of historical honesty is needed here, conceding nothing to the faith: the Eucharistic interpretation of the Fractio Panis is the traditional and most probable reading — that of its discoverer, Joseph Wilpert (Fractio Panis, 1895) — specified by Franz Wieland (Mensa und Confessio, 1906, p. 139): a Eucharist celebrated in connection with the funerary agape, at an anniversary Mass (sacrificium pro dormitione) for the deceased buried in the chapel^[21]. Prudence of speech changes nothing of the underlying conviction: the Eucharist is, throughout the art of the catacombs, omnipresent by allusion — bread, wine, fish and vine all converge towards the altar.

The Chi-Rho (☧) superimposes the first two Greek letters of the word Christós: Χ (chi) and Ρ (rho). It is a signature: to write these two intertwined letters is to inscribe the name of Christ.

The Chi-Rho is often framed by two letters: Alpha (Α) and Omega (Ω), the first and last letters of the Greek alphabet. They translate a word of the Apocalypse:

"I am Alpha and Omega, the first and the last, the beginning and the end." — Apocalypse 22:13^[22]

The message is dense: he who rests here belongs to Christ, master of beginning and end, and therefore also of this death which is but a passage. Historically, the Chi-Rho predates Constantine as a Christian abbreviation; it was its imperial adoption, after the vision at the Milvian Bridge in 312, that carried it from discreet sign to public emblem^[23]. In the catacombs, it marks the moment when the Church gradually steps out of the shadows.

Two birds borrowed from ancient culture express, in the catacombs, the hope of the resurrection of bodies.

The peacock was reputed to have incorruptible flesh. St Augustine reports having verified this belief himself, and draws from it an argument for the resurrection of the flesh:

"The flesh of the peacock… after remaining for as many days as would make any other meat putrid, was brought to me and found to be without any bad smell." — St Augustine, The City of God, XXI, 4^[24]

The phoenix, that legendary bird reborn from its ashes, serves from the end of the 1st century as an image of the resurrection. St Clement of Rome makes it an argument in his letter to the Corinthians:

"Shall we then esteem it to be a great and marvellous thing, if the Creator of the universe shall bring about the resurrection of them that have served Him in holiness…, when even by a bird He shows us the greatness of His power to fulfil His promise?" — St Clement of Rome, Epistle to the Corinthians, 26^[25]

Peacock and phoenix are therefore not decorative fancies: they are arguments of hope, images in the service of the dogma of the resurrection of the flesh.

The narrative heart of the art of the catacombs is a repertoire of scenes in which God delivers his faithful from certain death. Read on a tomb, they become a typological prayer: as you saved that one, save him who rests here.

Jonah, the sign par excellence

Jonah is the most widespread scene, sometimes developed in several panels: swallowed, cast up, then resting under the gourd. Christ himself gave the key to its meaning: "For as Jonas was in the whale's belly three days and three nights: so shall the Son of man be…" (Matthew 12:40)^[26]. The deceased is placed under the sign of Jonah: he sleeps in the earth as Jonah in the abyss, waiting to be restored to life.

Daniel, the three youths and Noah

Daniel as orant between the lions, the three young Hebrews unharmed in the furnace, Noah stretching out his arms from the ark: these scenes hammer home the same message^[27]. The just man threatened by imminent death is saved not by his strength, but by the faithfulness of God. Noah adds the baptismal dimension: saved through water, he prefigures the Christian saved by baptism — which closes the loop with the symbol of the fish.

Lazarus, Moses, Isaac, Susanna

The raising of Lazarus is the most explicit: Christ before the tomb, calling the dead man out, is the direct proclamation of what the Church hopes for each of her dead^[28]. Moses striking the rock makes the water of salvation gush forth; the sacrifice of Isaac shows the son spared, figure of the Son delivered up; Susanna, falsely accused then vindicated, becomes the image of the innocent soul defended by God.

The Catacomb of Priscilla preserves a fresco often described as the oldest known image of the Virgin and Child, dated to the late 2nd or early 3rd century^[29]. Mary holds the Child; beside them, a standing figure points to a star.

The identification of the figure with the star remains debated: it is recognised by turns as the prophet Balaam ("a star shall rise out of Jacob", Numbers 24:17), or as Isaiah^[30]. Caution is therefore required on details, but the essential holds: from the earliest Christian generations, Mary has her place on the walls where the dead are prayed for. The mother who gave the Saviour to the world also watches over the sleep of the faithful.

What the catacombs hand down to us is not a museum of dead signs, but a way of believing. For the first Christians, the fish, the anchor or the dove were not logos: they were miniature confessions of faith, worn even on their rings. Clement of Alexandria explicitly recommended it:

"And let our seals be either a dove, or a fish, or a ship scudding before the wind, or a musical lyre… or a ship's anchor." — Clement of Alexandria, The Instructor, III, 11^[31]

He discouraged instead the faces of idols, the sword, the bow or the cup of drunkenness: the Christian symbol had to speak of peace, sobriety and hope. We can thus measure the coherence of an entire culture, which made every everyday object a reminder of Christ.

For the Catholic faith, this art is a precious witness: it shows a Church which, from the 2nd century, believes in the resurrection of bodies, honours Mary, venerates the martyrs, celebrates the Eucharist and baptises in water. The walls of the catacombs confirm in stone what the texts affirm in writing — a continuity that reductive readings of early Christian history struggle to explain. This heritage also leads directly to the great question of why the Church uses images and to the distinction between icon, idol and sacred image.

The symbols of the catacombs are the first illustrated catechism of the Church. Discreet out of prudence, they are dense with faith: a fish confesses Christ there, an anchor speaks hope there, a shepherd carries the dead towards life.

Three traits dominate. First, hope: none of these signs celebrates death; all proclaim deliverance and resurrection. Next, sobriety: the Church expresses her mysteries by allusion, faithful to the discipline of the secret. Finally, doctrinal coherence: baptism, Eucharist, resurrection of the flesh, veneration of Mary and of the martyrs are already there, painted on stone, long before the great councils.

To read the catacombs is therefore to hear the oldest voice of Christian art — a voice which, from the depths of the earth, speaks only of light.

• Read the Christian catacombs of Rome: the history, architecture and martyrs of these underground cemeteries.
• Read why the Church uses images: the theological foundation of sacred art.
• Read the difference between icon, idol and sacred image: to distinguish veneration from idolatry.
• Read Christ Pantocrator: how the image of Christ unfolded after the symbolic art of the catacombs.