Tucked away next to the Forum, the charming little church of Santi Cosma e Damiano (Saints Cosmas and Damian) is one of Rome’s better kept secrets. The church is dedicated to twin brothers from the eastern Mediterranean, two doctors who were martyred at the end of the 3rd century. Unlike their modern counterparts, the brothers accepted no payment for the services they provided. One of these, allegedly, involved transplanting a black leg onto a white body. Consequently, Cosmas and Damian have become the patron saints of both doctors and surgeons. The cult of the two doctor-saints became very popular in the middle-ages when the belief grew up that any sick person who slept overnight in the church might be granted a dream leading to a cure.
Santi Cosma e Damiano was one of the first churches to use pagan structures in its design. Dating back to the early 6th century, the church incorporated both the so-called Temple of Romulus (4th century CE) and part of the Temple of Peace (1st century CE). The Temple of Romulus was not named after the legendary founder of Rome, but the young son of the emperor Maxentius, who died in 309 CE. It is now thought by many scholars to have been the Temple of Jupiter Stator. The ancient brick wall to the left of the entrance once sported the famous Forma Urbis Romae, a huge map of Rome incised into 150 marble slabs. The map measured 18 by 32 metres and depicted, in detail and to scale, the city of Rome at the beginning of the 3rd century CE. Only ten percent or so of the marble slabs have, so far, been recovered.
Both the church and the adjacent convent were radically restored and remodelled in the 1630s by Orazio Torriani and Luigi Arigucci at the behest of Pope Urban VIII (r. 1623-44). The pope was a member of the Barberini family, whose heraldic bees are prominently displayed throughout the church. The floor was raised 7 metres (23 feet), three chapels were added to either side of the nave and a new wooden ceiling and high altar were installed. The latter, unfortunately, rather obscures the view of the mosaics in the apse.
The mosaics, which clearly inspired those in Santa Prassede, are some of the oldest to have survived in Rome. In the centre of the apse we see Christ at his Parousia or Second Coming. Dressed in a golden toga and standing against a carpet of red clouds, he raises his right hand and holds a scroll in his left. He is flanked by St Paul and St Peter, who are presenting St Cosmas and St Damian (each bearing the crown of martyrdom). On the far left we see Pope St Felix IV (r. 526-30), who, as its founder, holds a model of the church, while on the far right St Theodore holds a martyr’s crown. The figure of the pope only dates back to the 17th century. Look closely at the flowers by his foot and you will see the Barberini's triad of bees.
Below Christ there is, what would become a very familiar format, an image of the Agnus Dei accompanied by twelve lambs/apostles. It stands on a mound from which flow the four rivers of paradise.
The mosaics on the apsidal arch depict scenes from the first chapters of the Book of Revelation. In the centre we see a medallion with the Agnus Dei reclining on a bejewelled throne, beneath which lies the scroll of the seven seals. The medallion is flanked by seven candlesticks, which represent the seven churches of God, and four angels. In the upper left corner, a winged man symbolises St Matthew, while in the upper right corner an eagle symbolises St John. The symbols of the other two evangelists disappeared when the chapels were added.
The wooden ceiling, part of Urban VIII's remodelling of the church, was painted by Marco Tullio Montagna. The ornate Baroque high altar (1637), which partly obscures the mosaics, is the work of Domenico Castelli. However, the image of the Virgin and Child dates back to the 13th century.
Santi Cosma e Damiano was originally entered from the Forum, which we can see through the plate glass window at the back of the church.