A lot of people think they can do my job. If we advertise for an assistant curator, you would be surprised the sort of people who apply, who have no idea what the job entails. You have to be a trained art historian with a keen interest in objects and connoisseurship.

Being a curator was something I fell into. I went to college to study theatre design and I started to take art history as well and got hooked. I did not know at that stage whether to teach or work in a museum. As a curator, you are trained alongside academics through graduate school.

I would have been jumping up and down trying to get the National Gallery to do the Caravaggio exhibition, if I had been here at the time. But it was planned and agreed with Naples four years ago, before I came. I inherited the project, came in and realised it.

The Supper at Emmaus pictures have never been shown side by side before. I had seen them in the same exhibition, but never with that brilliance of walking into the same room with them together. There were the same cast of characters, yet they could not be more different. I gave a lecture on the comparison of the two. I said that if you were to give them to undergraduates as a slide comparison, you might be forgiven for thinking they were from different artists. You can talk about the differences between the two paintings, but ultimately you have to feel it.

The earlier Supper was painted when he was a young artist, and the second five years later. But when you think he died a few months short of his 39th birthday, what would he have gone on to achieve?

We had not expected crowd issues with only 16 paintings in the exhibition, but it has been incredibly popular with the public, and people do not want to leave. For a curator, this is heaven.

When I am in the exhibition, I stand back and watch people. Some are in tears; everyone is engaged. You go into these packed rooms and it is quiet. It is very unusual for the public not to be chatting; it is the art professionals who chatter. When I have been in the gallery with visitors, I have been asked to be quiet. There is a certain mood and people are concentrating. Not long after it opened in Naples, a man under house arrest was nabbed waiting in the queue to see the Caravaggio exhibition.

Was Caravaggio a believer? At the beginning of the 17th century, yes, he would have been, in that it was part of everyone’s world outlook. He had a real brilliance, and did not just examine the biblical text but the greater cosmic significance. He gets very emotional, but I can’t really say whether it comes from a profound religious belief. But he is a very brilliant and thoughtful artist.

The Raising of Lazarus was the toughest painting to land, and The Adoration of the Shepherds (both from the Museo Regionale, Messina). We are sending them one of ours on loan as a thank you.  The way Caravaggio sets up the composition of this picture is so dramatic. In the struggle, Lazarus assumes the cross position.

My family were not remotely into art. I grew up in Miami, Florida. We went to church every Sunday and so had a background in Bible stories. There is not the same level of knowledge of the Bible around now. With young schoolchildren who come to the National Gallery, it’s only those from Evangelical Christian communities who do not need the stories explaining to them.

At the moment I am not reading anything that is not associated with my next project: Diego Velazquez the Spanish 17th-century painter. There are nine collection curators here, and we do spar about the relative greatness of our figures.

I am at my happiest working here because I have one of the greatest collections in the world. I was previously working for a museum in the buying game, but that started almost two centuries after the National Gallery. 

I am a visual hedonist, and when I am not working, I am enjoying exploring London and beyond. When I worked at the John Paul Getty Museum in LA, I explored the desert areas, which my friends in New York could not believe. I love St Martin-in-the-Fields, and the little church at Burnham Thorpe in Norfolk, where Nelson’s two standards are.

As a child, I thought I would probably go into acting. When I went to college, I did not consider I had a distinctive academic record, but I was determined to stay out of the Vietnam War and not be a part of it. Whenever I see a brilliant theatrical production, I think what might have been.

Nothing goes to the heart as a great painting does. My mother, who is now 88, and knows very little about art, has always said that as a child, I would look for hours at the still image — even though my father was a motion-picture projectionist and I had access to lots of films. I think the still image involves more of the imagination.

The Caravaggio exhibition is open from 10 a.m. to 9 p.m. today and Sunday (when it finishes) and from 10 a.m. to midnight on Saturday.