Gesù Nuovo

Put your hand against the wall in front of you. The stone is grey, cool, and slightly rough. Every block has been cut into a sharp little pyramid that points straight at you. Hundreds of them run across the whole front of the building, row after row. In the morning, each point throws its own small shadow. The effect is strange for a church. It looks less like a house of prayer and more like a fortress. There is a good reason for that.

This is the church of Gesù Nuovo, the New Jesus, in the old heart of Naples. That fortress face was never meant for a church at all. It began as the front of a private palace, built in the late fifteenth century for the Sanseverino family. They were among the most powerful noble houses in southern Italy. The princes of Salerno lived behind these stones. They wanted a home that told every passer-by exactly how strong they were.

The stone itself is called piperno. It is a volcanic rock quarried around Naples, dark grey with small flecks and streaks. You will see it all over the old city, in doorframes, staircases and pavements. The cutting style is called diamond-point rustication. Rustication simply means stone left deliberately heavy and textured, instead of smooth. Here the masons shaped every block into a faceted point, like a cut gem. It was a bold Renaissance fashion, and very few buildings in Naples carry it on this scale.

Now look more closely at the blocks. On many of them you can find small carved marks. Some look like letters. Others look like simple signs or symbols. Most historians think they are masons' marks, the private signatures that stonecutters used to identify their work. But Naples loves a mystery, and the marks have collected stories for centuries. Every guide in the square will have a favourite version.

Legend has it that the symbols were meant to be magical. According to one popular tale, the masons were asked to carve signs that would draw good fortune into the palace. Then they carved them the wrong way round, and the luck turned bad. Locals point to what came next. The Sanseverino family fell out of royal favour and lost the palace. More recently, some researchers have suggested the marks could even be read as musical notes. None of these readings is proven. That is part of the fun.

What is documented is the change of owner. In the late sixteenth century, the palace passed to the Jesuits, the Catholic religious order founded to teach and preach. They kept the old stone front and rebuilt everything behind it. The work finished around the turn of the seventeenth century. So the building you are facing has two lives. Outside, it is a nobleman's palace. Inside, it is a great Baroque church. Step through the doorway and see the difference.

The first thing most visitors notice is colour. After that grey stone, the interior is full of polished marble in red, yellow, green, white and black. Baroque is the style of the seventeenth and eighteenth centuries, and it aimed to overwhelm the senses with movement, gold and light. Here, almost every surface is inlaid, carved or painted. The floor, the chapels and the altars are all covered with patterned marble. Your footsteps echo differently in here, softer and longer.

Before you walk forward, turn around and look up above the entrance. That huge painting on the inside wall is by Francesco Solimena, one of the leading Neapolitan painters of the early eighteenth century. It shows a story from the Bible, in which a thief called Heliodorus is driven out of the temple in Jerusalem by a rider on a horse. Many people walk straight past it, facing the altar. Take a moment with it. The figures tumble down the steps in a great wave of cloth and limbs.

Now look up at the dome. The present dome is not the original one. Naples sits in an active volcanic and earthquake zone, and the church has suffered damage more than once over the centuries. The first dome was painted by Giovanni Lanfranco, a major artist of the seventeenth century. Almost all of his work up there was lost. What survives are the four corner sections below the dome, which show the four writers of the Gospels.

For many Neapolitans, the heart of this church is not the art. It is a doctor. Saint Giuseppe Moscati worked in Naples in the early twentieth century. He was famous for treating poor patients without charge, and for combining science with deep faith. He died in 1927, and the Catholic Church declared him a saint in 1987. His remains rest here, and people come every day to pray at his side chapel and ask for help with illness.

Follow the signs toward the rooms dedicated to him. You may find a wall covered in small silver objects. They are shaped like hearts, legs, eyes, hands and lungs. These are ex-votos, offerings left by people who believe their prayers for healing were answered. Each one is a private story of a sick body and a recovery. Nearby you can also see a recreation of his study, with his desk and some of his belongings.

There is one more surprise in those rooms. During the Second World War, Naples was bombed many times. In 1943, a bomb fell through the roof of this church and did not explode. Its casing is now kept on display. For many visitors, it sits beside the silver hearts and hands as one more small miracle. Whatever you believe, it is a sobering object to stand in front of.

When you are ready, step back out into the square. Let your eyes adjust to the light. In the middle of the piazza rises a tall, carved spire of white stone, dedicated to the Virgin Mary. Across the way stands the church and cloister of Santa Chiara. Behind you, the diamond points of the old palace are still catching the sun. Listen to the scooters, the voices and the church bells. Then run your fingers once more along those cool grey stones before you go.