Chant has been rebounding in popularity for some time now, ever since those Benedictine monks released their blockbuster recording several years back.

Now the Cistercians have gotten into the act — and they are also causing a musical sensation:

It isn’t every day that a group of Catholic monks find themselves on the pop charts. Yet that’s what happened to the monks of Stift Heiligenkreuz, a 12th-century Cistercian monastery near Vienna, whose CD of Gregorian chants has become a runaway hit.

After its European release in May, “Chant: Music for the Soul” became the top classical album in Britain before crossing over to the pop charts, at one point outselling recordings by Madonna and Amy Winehouse. Even before its U.S. release on July 1, the album became the most popular classical recording in this country, thanks to copious downloads on iTunes.

Call it divine intervention, or perhaps clever marketing on the part of Universal Records, which signed the monks to a recording contract after launching a search in Catholic publications in February. The record company had wanted to capitalize on the growing sales of chant music — which were due in part to the popularity of the video game Halo, which uses chantlike melodies in its soundtrack. Universal found the monks after their spokesperson, Father Karl Wallner, who also runs their theological academy and Web site, sent in a link to a YouTube video of their chanting that he had posted last September following a visit to the monastery by Pope Benedict XVI.

I spoke with Father Karl, 45, last week by phone about the growing interest in Gregorian chants, their spiritual significance and how he and his brothers are handling all the publicity.

This is music from 1,000 years ago, sung entirely in Latin, without accompaniment. Has the popularity of your CD surprised you?

Yes, very much. When we started (the project), we thought we would sell a few thousand copies, and now it’s a big success all over the world. I think what’s very impressive to us is that people are interested in our spirituality — because we are just doing what we do every day, singing three hours to praise God. And that’s the biggest success of all.

How do you explain the attraction of ancient, sacred music to a modern, largely secular audience?

I think it’s because the music is calm. It’s healthy. It’s touching. And you can feel that we sing it with some religious enthusiasm. People write me e-mails, and they say: “I feel touched by the finger of God when I’m listening to your singing.”

We can also see that people, even atheistic or agnostic people, are very much attracted by our way of living. Many of them come to us (the monastery) and they listen, they just sit back and listen. I think we are showing them as a religious community, by praising God, that our way of life represents something that has been lost to them. I know it’s something that many people in Europe feel they have lost.

How this CD came into being is an interesting “Old World meets New World” kind of story. Should we be surprised that monks like you are posting videos on YouTube and are generally pretty technologically savvy?

I don’t know what people in the outside world think about monks in the monastery, but we are men of the 21st century. We are living in a monastery, but we aren’t aliens or Neanderthals. According to the rule of St. Benedict and also that of the Cistercians written 1,500 years ago, every monk has to have something to write. And now the computer is the means by which we are writing. So everybody must know how to deal with the Internet, how to send e-mails. That’s quite normal for us.

Isn’t monastic life generally about disconnecting from the outside world to pursue a spiritual path without distractions, like e-mail?

It is, but this happens in other ways. Our liturgy is with the big tradition of the holy Church, and we are singing the Gregorian chants in Latin — yes, we are living in a very strict way. But, of course, we use the communication that is made possible by the Internet to promote the beauty of our vocation.

Has life at your monastery changed since the music came out?

Well, it’s changed for me and for Father Abbot, because we are both doing interviews with the press, and we have had some journalists at the monastery, but I think we are handling it quite well. For my other brothers life is the same. You have to believe me, none of them is really interested in where we are on the charts in England or France or Australia or the United States. I am occupied with those questions, but the other monks don’t even ask me about it.

I’m very proud that my brothers are not proud about being pop stars. I’m proud of them because it shows that our young community has a very good sense of what religious life means. It means being together with God and not taking care of the things of this world.

Check out the link for more. And if you visit Amazon, you can hear excerpts.