The Baldacchino and the Altar of the Chair of St. Peter's Basilica

By Johana Bronková

Upon entering the main nave of St. Peter's Basilica, one is struck by the immense scale of the space. Suddenly, everything seems to shrink, and we have a new perception of our surroundings, as if we are facing a majestic work of nature.

However, the architecture has its own order, and the gaze is immediately drawn to two focal points within the interior space: the papal altar with the baldacchino above the tomb of St. Peter, and the Chair Altar at the far end of the basilica.

Both relate to the basilica's patronage and offer an interpretative key to the attentive observer. Not only are they the work of the same artist, Gian Lorenzo Bernini, but the artist himself connects them to each other. From the moment one enters the basilica, it is evident that the monumental bronze baldachin frames, in perspective, the Altar of the Chair of St. Peter, located in the apse.

This is no coincidence: while the papal altar above the tomb of the Apostle—on which, like a rock, Christ promised to build His Church (Mt 16:18)—refers to the origins, to the early Church born from the testimony of martyrs (hence also known as the Confession Altar), the Chair points to the primary mission of Peter's successors: to proclaim the Gospel and instruct the People of God.

The Baldacchino

The baldacchino, an ancient symbol of authority and prestige, was designed by Bernini in 1624 as his first architectural commission and was completed—apparently with the engineering expertise of his future rival, the brilliant architect Francesco Borromini—in 1633.

The challenge entrusted to him by Pope Urban VIII, whose heraldic figures—the bees—are found in various forms throughout the baldacchino's decoration, was primarily to create an architecture that would match the monumental scale of the Church.

To avoid making the structure appear overly bulky, Bernini opted for twisted columns. Moreover, their shape and decoration are linked to the so-called "Holy Column," preserved today in the Treasury Museum of St. Peter’s—a twisted column believed for centuries to have witnessed Jesus's preaching in the temple of Jerusalem.

Together with similar columns, some of which are still seen in the Loggia of the Relics above the balconies in the pillars, they adorned the 4th-century pergola above Peter's tomb in the ancient basilica.

Bernini’s ingenious composition, however, combines the idea of a ciborium as a solid architectural structure with the original meaning of a baldacchino as a decorative drapery over an important place or figure. He integrates bronze drapes directly with the columns and uses a lightened construction of curved ribs completed by the iconographic motif of palm branches, seemingly supported by dynamic angelic figures.

The undulating lines of the baroque architecture culminate in the cross atop the gilded globe at the baldacchino’s summit, embodying the ancient saying: "Stat Crux dum volvitur orbis"—The cross stands firm as the world turns.

The Altar of the Chair

In a way, the Baroque Era was much like our own. In modern terms, it could be called multimedia in its pursuit of using various artistic techniques to engage all human senses, to involve the viewer to the point of breaking down the barriers between subjective and objective, making them participants in a new reality, a living element of a “beautiful synthesis,” a vision of the universe animated by the Spirit of God.

An example—or almost a prototype—of this transformed reality, conscious of divine presence, that bursts into our space uniting heaven and earth, is the apse of St. Peter's Basilica.

The entire back wall of St. Peter’s Basilica forms a true scene in which Bernini unfurls before our eyes an astonishing vision.

Even during the work on the baldacchino above the tomb of the Apostle Peter, Bernini's contemporaries were calling him the “Michelangelo of our century,” and now, commissioned by Alexander VII, he proves that those words were not mere flattery.

If, in Michelangelo's concept of the apse of the new Vatican Basilica, light played a crucial role as an equal counterpart to the modeled mass of masonry, Bernini perfected this sculptural principle by composing a vision of the heavens opened.

From this opening, a dove symbolizing the Holy Spirit, bathed in light, emerges, with angels flying around it amid clouds. From this vision descends an enormous bronze throne, concealing a much smaller one beneath it, on which, according to tradition, St. Peter would have preached. The ancient seat, decorated with ivory plaques depicting the Labors of Hercules, arrived in Rome in the 9th century as a gift from the Frankish King Charles II the Bald to Pope John VIII, though some elements like the panels likely date to an earlier period.

Some might view Bernini’s composition as a kind of colossal reliquary, but perhaps this isn’t the main point. Indeed, the monumental scene, crafted between 1657 and 1666, recalls the unchanging mission of Peter's successors: to proclaim Christ, interpret, and teach the Word of God.

That is why above Peter’s chair hovers the symbol of the Holy Spirit, who leads us into all truth, the Spirit who is Comforter and Intercessor (Jn 14:17, 14:26, 16:13), but also inspires the right words in times of crisis (cf. Lk 12:12).

On either side of the throne are four prominent theologians: St. Ambrose and St. Augustine, Fathers of the Western Church, and St. Athanasius and St. John Chrysostom, Fathers of the Eastern Church, who, with a gentle gesture, almost with their fingertips, seem to lift the throne.

The bronze chair is itself adorned with reliefs of three gospel scenes illustrating the papal mission as Christ’s representative on earth: "Feed my sheep" (Jn 21:17)—entrusting the human flock to Peter; the Washing of the Feet (Jn 13:14)—demonstrating the nature of his ministry; and, finally, the Delivery of the Keys to the Kingdom of Heaven (Mt 16:19).

The immense throne, too large for any human, shows that it is not up to humanity to decide who will sit upon it.