Not so fast: Sister Joan Chittister argues that we should not be so quick to abandon the practice of going hungry during Lent and throughout the year.

I FIRELAND IS A BELLWETHER OF ANYTHING TODAY, IT is surely of the Catholic consciousness. The Angelus still plays on public TV and radio at noon and 6 p.m. everyday. "Stations"--house Masses that developed during penal times when the practice of Catholicism was forbidden by British law--are still practiced in rural areas. St. Brigid's Day is even more of a celebration in some ways than St. Patrick's Day.

But don't be deceived. All is not traditional anymore. When the waitress took our orders in a little village restaurant in the west of Ireland, for instance, she didn't know how to respond to my request that the chef wrap a starter of goat cheese in something besides ham. "The meat," I explained. "It's Lent." She looked puzzled, raised her eyebrows, and scurried away from the table, confused and embarrassed.

I was in Ireland in Lent 2006, and the Friday fast meant absolutely nothing. And why was I surprised?

The Challenge of Peace, the 1983 peace pastoral from the U.S. bishops' conference, called on Catholics to return to the Friday fast as an act of penance for peace. They wrote: "We call upon our people voluntarily to do penance on Friday by eating less food and by abstaining from meat. This return to a traditional practice of penance, once well observed in the U.S. church, should be accompanied by works of charity and service toward our neighbors. Every Friday should be a day significantly devoted to prayer, penance, and almsgiving for peace."

Almost no one I know is doing it. The question is: Should we? And if we should, why aren't we?

FASTING HAD A GREATER EFFECT ON ME IN MY CHILDHOOD than something as significant as trans-sub-stan-ti-a-tion." Transubstantiation, they told me, was the changing of the bread and wine into the Body and Blood of Christ. But that I took for granted. Fasting, on the other hand, this foreign way of going about life, was something that called for real change in the way I lived.

In the Eucharist, Jesus changed for my sake. In fasting, I was being called to change for something far beyond my own sake. Fasting made a kind of demand on me that few other things ever did.

What it was and why anyone would do it became an even more important question as the years went by. Most of all, if the practice of fasting was so good, why had it disappeared?

When a practice strays far from its original intentions, it often must disappear so that it can be rediscovered for the right reasons. Fasting is certainly one of those practices.

I remember as a youngster dining in a convent during Lent and being curious about the small set of brass scales between every four place settings. "That's for weighing our food during Lent," the nun showing us the house explained.

Years later I entered a monastery myself. But there were no scales on the tables. The Rule of Benedict taught that we were to fast during Lent, true, but added that we were also to "add to the usual measure of our service something by way of private prayer" and "holy reading and almsgiving."

NOW THERE WAS A TWIST. CLEARLY FASTING WAS ABOUT something more than simple deprivation. Obviously fasting was supposed to add something to our lives as well as to take something away. It was meant to sensitize us to life more than it was to deprive us of it.

But when fasting was no longer defined as a "mortal sin," it disappeared overnight. Fasting for my generation became more burden than blessing, more an attempt to punish the body than an invitation to strengthen the soul. We managed to concentrate on beating the body down rather than showing the value of emptying ourselves of clutter so we could concentrate on something besides ourselves.

Fasting over the centuries became a kind of mathematical legerdemain of the soul. Meals had times, lengths, and quantities attached to them. The scales kept portions under 4 ounces; the distinction between juices and soups and solids kept us paranoid about the differences between them. If heaven and hell depend on it, a person can get very nervous. No wonder modern psychology found fasting suspect. It had lost all semblance of sense for the heart or gift for the soul.

When Vatican II came along with its emphasis more on spirit than rules, people put down some rules immediately. Fasting, for obvious reasons, was one of them.

But the practice of fasting cannot be easily dismissed. Fasting is the unfinished chapter in post-Vatican II spirituality because the reasons for it abound.

The place of fasting in the lives of all the great spiritual figures in history brings no small amount of weight to the subject. Time, too, recommends we revisit the subject, as fasting has been a constant tradition in the church for 20 centuries. Finally, the presence of fasting in all spiritual traditions, not just Catholicism, makes a person pause. In all places and times, fasting has been a hallmark of the person on a serious search for the spiritual dimensions of life.

HOW DO WE EXPLAIN THE MEANING OF FASTING IN OUR time? The answers ring with the kind of simplicity and depth common only to the holiest of disciplines. The fact is that the values of fasting strike to the heart of a person, sharpen the soul to the presence of God, and energize the sprat in a way engorgement never can.

Fasting calls a person to authenticity. It empties us, literally, of all the non-essentials in our lives so we have room for God. It lifts our spirits beyond the mundane.

Fasting confronts our consumer mentality with a reminder of what it is to be dependent on God. It reminds us that we are not here simply to pamper ourselves. We are, indeed, expected to be our brother and sister's keeper. We know why we are hungry. We voluntarily gave up the food we could have had. But why are they hungry? Where is the food they should be eating? And what can we do to fill them now that we are done filling only ourselves?

Fasting opens us to the truth. It makes space in us to hear others, to ask the right questions, to ingest the answers we have been too comfortable to care about for far too long. It makes room for adding "to our service a bit more prayer and reading and almsgiving," as the Rule of Benedict says.

Fasting requires us to develop a sense of limits. No, we may not have it all, do it all, and demand it all. Our needs do not exceed the needs of others, and our needs may never become more important than theirs.

Fasting teaches us to say no to ourselves in small things so that we may have the strength to say no to those people and systems and governments who want to use us to shore up their own power and profit despite the needs of others.

When we fast, we become voluntarily poor and so understand the needs of the poor.

When we fast, we say yes to the Spirit and no to the lusts within us that drive us to live for money and power and profit and the kind of engorgement that renders the rest of the world destitute.

No doubt about it: Fasting surely has something to do with peacemaking. It puts us in touch with the Creator. It puts us in touch with ourselves. It puts us in touch with the prophet Jesus who, fasting in the desert, gave up power, wealth, comfort, and self-centeredness, and teaches us to do the same. It puts us in touch with the rest of the creation whose needs now cry out in our own.

Now we can finally feel the emptiness of others. Now we can at last know their pain. Now we can stand in solidarity with all those in the world who do not have the luxury of fasting but who know the awful uncontrollable hunger of it.

Now we must ask ourselves what it is about us that must change so that they can be filled.

Indeed, when we fast, we come to know a little better what transubstantiation is really all about. This time it is about changing a bit more of ourselves into the Body and Blood of Christ.

ARE THE BISHOPS RIGHT? SHOULD WE BE FASTING ON FRIDAYS during Lent or throughout the year? It all depends. If we are willing to understand fasting more as the spiritual art it has always been than as some kind of confessional arithmetic designed to buy our way into heaven, we may once again become the people fasting is meant to make us. Then, empty of the excesses of the self, we will be ready to hear the needs of others with such clarity that wars for oil, wars for power, wars for personal profit will be impossible to abide.

What if they gave a war and nobody came? No. The question really is: What if they fasted and so finally had the insight and the strength to refuse to come?

SISTER JOAN CHITTISTER, O.S.B., founder of Benetvision, a resource and research center for contemporary spirituality. She also writes and speaks on issues facing Catholics today. Her most recent book is The Ten Commandments: Laws of the Heart (Orbis).