Walk into the medieval and early Renaissance rooms of the National Gallery in London and you pass, within a few paces, a lamb tucked under a saint’s arm, a white lily standing in a jar, a human skull grinning up from the foot of a cross, and an old man clutching a heavy bunch of keys. A modern visitor tends to read these as decoration or stage props. To the men and women who first knelt before these panels, they were closer to words. Western Christian painting ran on a shared vocabulary of signs, precise enough that a worshipper who could not read a line of Latin could still read a picture with confidence.
That vocabulary has not changed. Learn a handful of its core terms and the Old Master collections stop being a parade of pious scenes and become something you can decode. Four signs do most of the heavy lifting: the lamb, the lily, the skull and the keys. Master those and much of the story of Western painting opens up.
Why the Old Masters speak in code
For most of the medieval and Renaissance period the audience for religious art was largely unlettered, and pictures did the teaching. Saints were given recognisable objects, known as attributes, so that a congregation could identify them at a glance. More than labels, these attributes gave each saint a distinct visual personality, so that a worshipper who could not read a word could still recognise the scene before them.
The modern decoder ring for all of this is James Hall’s Dictionary of Subjects and Symbols in Art, first published by Harper and Row in 1974 with an introduction by Kenneth Clark. It remains the standard handbook, and it works because the symbolism was systematic. A lily meant one thing, a skull another, and painters could set them side by side to build a sentence.
The lamb – sacrifice made visible
The lamb is the oldest and most loaded of the four. Its meaning comes straight from the Gospel of John, where John the Baptist sees Christ approaching and names him the Lamb of God “which taketh away the sin of the world”. The animal stands for Christ himself, and specifically for his sacrificial death: the unblemished lamb of Old Testament ritual, offered up for others.
No painting states this more completely than the Ghent Altarpiece, the vast polyptych begun by Hubert van Eyck and finished by his brother Jan in 1432, still in St Bavo’s Cathedral in Ghent. Its central panel shows a lamb standing on an altar, a wound in its breast streaming blood into a golden chalice, adored by ranks of saints, martyrs and pilgrims. The inscription above reads ECCE AGNUS DEI QUI TOLLIT PECCATA MUNDI, “Behold the Lamb of God who takes away the sins of the world”. Below, the Fountain of Life runs with water the picture presents as fed by the Lamb’s own blood. The whole immense work is a single argument about redemption.
Londoners have a closer example. In the Wilton Diptych, painted around 1395 to 1399 for Richard II and now in the National Gallery, John the Baptist presents the kneeling king to the Virgin and Child. John, Richard’s patron saint, cradles a small white lamb against his chest. Just as Mary holds the Christ Child, John holds the Lamb of God, the same figure in another form. One variation is worth carrying with you: when the lamb bears a banner topped with a cross, its meaning shifts from sacrifice to triumph, the sign of the risen Christ.
The lily – purity and the Annunciation
The lily is far narrower and almost always points one way, to the Virgin Mary. The flower is the Madonna lily, Lilium candidum, a tall white lily grown around the Mediterranean since antiquity. Its whiteness carries the message. By the medieval period the white lily had become the fixed emblem of Mary’s purity and virginity, which is exactly how it earned the common name Madonna lily.
Its natural home is the Annunciation, the moment the archangel Gabriel tells Mary she will bear God’s son. According to the Metropolitan Museum of Art, by the 14th century it had become common to find the lily in Annunciation paintings and illuminations, sometimes held out in Gabriel’s hand, sometimes standing in a vase between the two figures. Leonardo da Vinci’s early Annunciation in the Uffizi shows the kneeling angel holding a stem of white lilies, an unmistakable label for the woman he addresses.
Annunciations reward close reading because painters loaded them with more than the lily. Carlo Crivelli’s Annunciation with Saint Emidius, dated 1486 and hanging in the National Gallery, sends the Holy Spirit down as a thin golden ray of light that pierces the wall of Mary’s house to reach her. In a cage on that wall Crivelli perches a goldfinch, a bird carrying its own grim forecast, which we come to below. Nothing in these pictures is idle.
The skull – death, Golgotha and the vanitas
A skull is a memento mori, from the Latin for a reminder that you must die. It presses the viewer to weigh the shortness of life against the fate of the soul. Set beside a scholar or a penitent, such as Saint Jerome at his desk or Mary Magdalene in the wilderness, it marks a mind fixed on eternity rather than the world.
At the foot of a Crucifixion the skull becomes precise. The hill where Christ died was called Golgotha, which the Gospels gloss as the place of a skull; Jerome rendered it in the Latin Vulgate as calvariae locus, the origin of the word Calvary. Medieval tradition held that the buried skull of Adam, the first man, lay directly beneath the cross, and that Christ’s blood ran down the wood to fall upon it. When you see a single skull among the rocks below the cross, that is Adam, and the picture is telling you that the second Adam has redeemed the first.
The skull’s most concentrated afterlife came in the Dutch Republic, where 17th-century painters built a whole genre, the vanitas still life, around it. Skulls, guttering candles, watches and soap bubbles were arranged to preach the theme of Ecclesiastes, “vanity of vanities, all is vanity”. Britain’s most famous skull belongs to this line of thinking. In Hans Holbein the Younger’s The Ambassadors of 1533, in the National Gallery, two confident French envoys, Jean de Dinteville and the young bishop Georges de Selve, stand among the instruments of learning and worldly power. A strange grey smear crosses the floor at their feet. Step to the right of the picture and it snaps into focus as a human skull, painted in stretched, anamorphic perspective. Every achievement displayed above it is measured against that one distorted shape.
The keys – authority and Saint Peter
The keys are the easiest sign to use, because they identify a single man. They belong to Saint Peter, and they come from a specific promise. In the Gospel of Matthew, Christ tells him, “I will give unto thee the keys of the kingdom of heaven”, handing Peter the authority to bind and to loose. From then on he is almost never shown without them.
Usually there are two, and often one is gold and one silver: by tradition the gold key stands for spiritual authority in heaven and the silver for authority on earth. The same crossed keys sit on the arms of the papacy, whose popes claim their descent from Peter. For the gallery-goer the practical value is blunt. In any crowded scene of apostles or saints, the figure holding keys is Peter, every time.
The founding image is Perugino’s fresco Christ Giving the Keys to Saint Peter, painted in 1481 to 1482 on the wall of the Sistine Chapel. A kneeling Peter reaches up to take the keys from Christ while the other apostles look on, the scene laid out with the calm, measured spacing that would shape the High Renaissance. The subject mattered enormously in Rome, because it was read as the biblical charter for the authority of the popes.
A working vocabulary
Once the four big signs are secure, the smaller ones fall into place, and this is where a slice of wider visual culture becomes genuinely legible. A dove descending is the Holy Spirit. A goldfinch in the hands of the Christ Child, as in Raphael’s Madonna of the Goldfinch where the infant Baptist holds the bird out to him, foretells the Passion, because the thistle seeds the bird eats linked it to Christ’s crown of thorns. A peacock stands for immortality. A pomegranate split to show its seeds, held by the Virgin or Child in works such as Botticelli’s Madonna of the Pomegranate, points to the Resurrection and the gathered Church.
Saints keep their name-tags too. Catherine of Alexandria has the spiked wheel on which she was tortured; Sebastian is pierced with arrows; Jerome keeps a lion and a cardinal’s hat; Mary Magdalene carries a pot of ointment. The Wilton Diptych alone hands you two more: Edmund holds the arrow of his martyrdom, and Edward the Confessor a ring. None of this is ornament. Each object is a caption.
Reading the room
The reward for learning this vocabulary is not academic. It changes what a gallery is. The Old Master rooms of the National Gallery were built to be read, not merely admired, and once the lamb, the lily, the skull and the keys become second nature, the pictures stop being silent. A white flower tells you a virgin is about to hear extraordinary news. A bunch of keys names a fisherman given the run of heaven. A grey smear on the floor of a portrait reminds two ambassadors, and you, how the story ends. The paintings were always talking. It takes only four words to start hearing them.
Image: Jan van Eyck, The Arnolfini Portrait (1434), National Gallery, London – a painting dense with Christian symbolism. Public domain, via Wikimedia Commons.
