Sisters Carolyn and Rachel are among the more than 3,800 Roman Catholic nuns in the United States who have removed themselves from the distractions of a worldly life to the cloister, devoting their lives to the search for God through prayer. It is not a self-centered meditation. They believe that their union with God contributes to the salvation of all people, and that their prayers for humanity touch the lives of the suffering everywhere. In an earlier century, they might have been respected by families and friends as women with an exceptional calling. Today, they are often viewed as rebels by a secular society that values action over contemplation. Their special way of life sets them apart in a world where even many Catholics dismiss the cloister as an archaic institution and the nuns inside as people with an unhealthy attraction to solitude - weak women who are not carrying their weight in the world.

Sister Marjorie Robinson, 35, former teacher from Philadelphia and now a Carmelite at the Beacon cloister, recognizes that "to our society, it's almost like we're marginal people, a countersign to a lot of what our society goes after - the practical and the material." What she and her sisters are saying, however, she points out, is that "there are deeper realities - something beyond the everyday illusions and distractions." As a symbol of her permanent commitment to God, she, like many sisters, wears a plain gold ring inscribed with the word "Jesus," which she received at her final vows ceremony.

The timeworn image of cloistered nuns as escapists, spurned lovers or naive waifs has little basis in reality today. It takes more than a botched-up love affair to lure educated women in their 20's and 30's to the cloister in the 1980's. For many, choosing to leave behind family and friends, the possibility of marriage and children and worldly careers that offer tangible rewards is a long, difficult and frequently painful decision. And opting to stay in the cloister after all romantic notions about the life have been stripped away is tougher still.

Yet at time when almost three times as many nuns are leaving than entering active teaching, nursing and missionary orders each year, the number of cloistered nuns in the United States is slowly increasing. Some still elect to enter highly traditional orders as "brides of Christ," to live behind grilles, to walk barefoot and to practice penances, such as self-flagellation, that date back to the Middle Ages. A few seek even greater solitude in hermitages. But most of those who choose the contemplative life today gravitate toward orders whose broad interpretation of the guidelines set out by the Second Vatican Council have freed their members from the hair-shirt habits and the almost total silence of the past.

The wrong reason to enter any kind of cloister, says Sister Carolyn, "is to escape. It takes a certain amount of psyhic strength to face yourself and your reactions to the same people in a cloister 365 days a year. You go to the convent to find solitude, and you find God, and you find yourself."

The majority of the more than 200 Catholic cloisters in the United States today are offshoots of convents founded in Europe during the Middle Ages. The largest order - about 850 sisters in 65 convents - is the Discalced (shoeless) Carmelites, founded by St. Teresa of Avila in Spain in 1562 and brought to the United States in 1790. There are at least a dozen other major American cloistered orders, including the Poor Clares, the Sister Adorers of the Precious Blood, the Sacramentines, the Passionists, the Cistercians, the Redemptoristines and branches of the Dominicans, the Visitation Nuns and the Benedictines. While other Christian religions also have cloistered communities, their numbers are far fewer.

In all but two of the six American Catholic cloisters and the community of hermit nuns visited over a recent period of four months, it was possible to speak to the sisters without any physical barrier separating us. At one, conversations had to be conducted through a grille; at another, from behind the wooden turn used to pass items in and out of the convent. It was also possible to talk to some sisters on the telephone, although at times only after a call back from a message left on an answering machine, which is one order notifies callers that "The sisters are at prayer...remembering your intentions." More open discussions took place at a two-day meeting last September of the Metropolitan Association of Contemplative Nuns in Yonkers, N.Y. And during a visit this spring to Israel and France, several cloistered nuns on Mount Carmel and in Paris spoke of their concerns, the former, through a grille, the latter, face-to-face.

That the special role of the contemplatives has continuing relevance was emphasized by Pope John Paul II last November when he praised cloistered nuns in Spain for their devotion to absolute principle in a world that, he said, "exalts relative values."

BETWEEN A.D. 500 AND 1200, ALL NUNS were cloistered. Because a large dowry was generally required for entry, most of the sisters were daughters of the aristocracy. For centuries, a religious life was considered the respectable alternative to marriage. In many cases, it also offered women a more independent and intellectually stimulating life - in northern France and Germany, several orders were renowned for the academic level of the all-girls schools they operated.

During the late Middle Ages, the public began to view the cloister less as a holy institution and more as a dumping ground for the nobility's rebellious daughters, discarded mistresses and the widows of enemies. Some of these unwilling recruits were notorious for their neglect of religious duties and their general disregard for the vows of poverty, obedience and chastity. Although several Catholic reformers, notably St. Teresa of Avila, restored strict monastic order to dissolute convents, nuns never quite regained their exalted stature.

In the last century, a few former sisters have reinforced the negative image of nuns through highly publicized, sometimes factually suspect, accounts of cruel penitential practices in some North American convents. While some overly zealous convent heads may have stretched the concept of penance to extremes in the belief that intense physical pain and humiliation led to holiness, they were certainly exceptions. Film makers further colored the public's perception by sometimes protraying nuns as inane schoolgirls, ethereal creatures or despotic spinsters. Rarely have contemplatives been presented as mature women with a vocation as challenging as any other "career."

Before turning to cloistered life, Baltimore Carmelite Sister Barbara Jean LaRochester had spent 17 years as an active nun in Philadelphia. During the week, she worked as an X-ray technologist in a Catholic hospital and on weekends as a volunteer teacher's aide in an inner-city school. As a board member of the National Black Sisters Conference in 1968, she was active in the civil rights movement during the height of the race riots. But in 1972, she decided her real call was to contemplation.

"As a physcial presence out in the world I could only be one person with two hands and two feet," says the now 50-year-old nun. "But through prayer, I felt I could reach more of my brothers and sisters. The spiritual dimension is limitless."

For Carmelite Sister Annamae Dannes, the decision came 15 years ago, when she was 26 years old and well-launched on a career as a teacher in a northern Ohio public school. "When I was in school, I felt that if I dated the right person I'd be happy," she says. "After college, I thought that if I traveled in Europe I'd be satisfied. Then I got the idea that moving to New York City and going to Columbia Teachers College would be grand. Later, it was getting the right job. But, somehow, it was never enough,"

"I delighted in teaching, but I was beginning to question the meaning of my life. I have a friend who used to pray with the nuns at the Cleveland Carmelite and one day I joined her. I felt right at home here from the start. I just knew that was where I belonged."

Cloistered nuns believe that their vocation is to witness the primacy of prayer in the Church, to serve as a reminder of the contemplative dimension in all lives, and to intervene for others before God. "If people are aware that I'm praying for them," says Sister Michaelene Devine, prioress at the Beacon Carmelite, "it's a real source of of God." Desert Mother Mary of Jesus, who heads the Carmel of the Immaculate Heart of Mary, a hermitage in Chester, N.J., expresses the effect in terms of secular linkages. "People are conscious of radio, TV and the telephone," she says, "but they're not always conscious of this spiritual network of communication through prayer." Contemplatives, do not, however, says Sister Annamae Dannes, feel that their prayers have more weight than those of anyone else.

If the sisters come to the cloister to pray for the world, they stay because of the relationship they develop with God. Contemplation may be deep and mysterious, but it is not abstract.

"It's not a psychological mind-game we're playing," says Sister Rachel. "When we pray, we meet a real person - God. It's like a regular relationship with anyone. On some days, it's ecstatic. On others, I wonder how I ended up here."

"For prayer, you need silence and you need solitude," declares Sister Michaelene. "In community, we provide this for one another."

But just how cloistered a convent must be to facilitate prayer is a matter of debate among contemplatives. In affirming the role of the cloister in 1965, Vatican II stated that "it should be modified according to conditions of time and place, and outdated customs done away with." It did not, however, decree specific changes. Individual orders consequently reached different conclusions.

Until the 1960's, the inner-sanctums of almost all cloistered convents were cut off from the world by heavy iron or wooden grilles, some with sharp spikes pointing outward to discourage persistent lovers or distraught fathers. Nuns rarely left the convent grounds. Extern sisters, who were not part of the cloister, greeted visitors, answered the telephone, shopped for food and supplies and conducted other worldly business.

All contemplatives then wore heavy wool habits, whatever the weather. Some went barefoot, even in winter. Rules of silence were rarely broken, and then only after saying a prayer and kissing the floor. In some convents, nuns communicated much of the time in writing or through sign language.

The Mother Superior was the unquestioned leader of the community. The sisters had to ask her for permission for everything from getting supplies to staying up an extra hour. Mortification was considered an essential part of most cloistered life, and common penances included frequent fasting, kneeling during meals and praying for extended periods of time with arms outstretched.

After Vatican II, many communities decided it was time for a change. Some began with the convent building itself. One morning in 1969, the Yonkers Sacramentines voted to remove the grille in their front parolor, and by noon it was down, thanks to a sister who knew how to use an electric saw. "I was so happy," recalls Sacramentine Sister Mary of the Eucharist. "When my mother visited, I could hug her for the first time in years."

In all but the most traditional cloisters, the rules have been relaxed considerably. A sister my now leave the grounds alone to go to a doctor, to visit a sick parent, to shop or to vote. The emphasis is less on conformity and more on the intellectual, emotional and artistic development of each sister. A few nuns have even attended college classes.

Many traditional vows are differently interpreted today. Poverty does not mean going without nutritious meals or forgoing an occasional treat. According to Sister Michaelene, "It means respect and enjoyment of material things without being attached to them." Obedience no longer means asking the Mother Superior for "permissions." Rather, says, Sister Helen Werner, the 63-year-old coordinator of the Maryknoll cloister, "it means being accountable to God and the rest of the community." And the rule of silence is no longer "enforced." Instead, Sister Helen says, it is "looked upon as a value, but so is sharing in relationships."

For many nuns, sharing means communicating with other orders. In the past, one community had virtually no contact with another, even when their convents were within walking distance of each other. In 1969, 130 sisters from all over the United States gathered in Woodstock, Md., to form the Association of Contemplative Sisters. Today, the A.C.S., which meets every two years, has 400 members who pool their financial resources to sponsor workshops and lectures on theology, psychology and the role of the contemplative in the modern world.

"Getting together as a group of women with common needs," says Sister Annamae Dannes, president of the A.C.S., gave the nuns "the strength to stand up for themselves," in a male-dominated church.

Sisters are also communicating more with their lay neighbors. Some of them, says Sister Annamae, "hold prayer groups and act as spiritual counselors for people who want to talk about prayer or their lives in general." And in many cloisters, the chapel is open to the public during daylight hours and invited visitors may attend mass.

But the nuns say they try not to let these involvements disrupt their lives of prayer. "We want to stay in touch with the world and be available to people, but we can't get overly active," says Sister Mary Devereux, of the Blessed Sacrament cloister in Yonkers, N.Y., an order of perpetual adoration whose nuns keep a constant vigil of prayers in their chapel. "It's a constant struggle. We're living in the world, but we're not of it."

Perhaps no contemplative community is more aware of the world outside its walls than the Maryknoll cloister. The 12 nuns in the tan brick convent on the grounds of the Maryknoll Sisters' headquarters are all former missionaries who have spent at least two years in active service, a prerequisite for entering the order's cloisters. Their special calling is to focus their prayers on the more than 1,900 Maryknoll priests, brothers, sisters and layworkers in their "loneliness and struggles on the mission." In December 1982, two Maryknoll sisters were murdered in El Salvador.

In the mid-1960's, the role of the cloister was questioned by many within the Maryknoll community, as it was throughout the Catholic Church. Now, many Maryknoll missionary nuns on home leave go to the cloister to make a retreat. "When you're out on the mission," says Sister Muriel Vollmer, "you see your own helplessness. Very often the missionaries can't even work because they're so curtailed by governments. Many come home because they're on hit lists. You can't survive in these times without prayer."

THE PRAYERS BEGIN BEFORE dawn at the Carmelite's Beacon cloister, a modern, red-brick building overlooking a large pond on 30 secluded acres in the Hudson River Valley of New York. The 12 nuns in the community range in age from 35 to 84. A few of the older sisters still wear long, veiled brown habits. The rest dress in brown knee-length dresses or skirts and blouses. The routine at Beacon is similar to that at most cloisters. Before the first light of day, each sister rises to pray privately in her cell - a small cement-block room, simply furnished with a desk, chair and bed, above which hangs a large wooden cross - or in the chapel, a modern octagonal building.

At 7:15 A.M., the whole community gathers in the chapel to sanctify the day with the morning portion of the Divine Office, or Liturgy of the Hours, arranged so that the entire day is made holy by the praise of God. The office concludes with intercessory prayers, with each sister rising in turn to pray aloud for a particular person or group.

A local priest arrives at 8 A.M. to say mass. The nuns gather in the chapel again at noon, in the late afternoon and early evening for communal prayers. During the afternoon, another hour is spent in private contemplation. The nuns also pray silently as they work. Some clean and maintain the convent. Others earn money for the community sewing clerical vestments or by doing keypunching for the archdiocese. For the rest of their financial needs, they rely on donations. While their annual operating costs were not available, another cloister of similar size estimates its at about $60,000, which includes medical insurance and building maintenance.

The sisters at Beacon take turns preparing dinner, the one communal meal of the day, taken at 6 P.M. For an hour afterward, they may walk around the grouns, or, when the weather is warm, take a rowboat out on the pond. This is one of the few times during the day when they break their silence to share their thoughts.

In dramatic contrast to more open cloisters like Beacon are those that have left things much as they were in the Middle Ages. Tucked between rundown buildings in Brooklyn's Crown Heights section is a large white brick Carmelite convent enclosed by a 10-foot-high cement wall, the outside of which has been irreverently covered from top to bottom with graffiti. Amid the jagged colored glass scattered on top of the fortress-like wall stand two larger-than-life-sized statues of Jesus Christ and the Virgin Mary.

The rare visitor who is buzzed into the front parlor of the convent - the security system is a concession to the realities of 20th century urban life - will never actually see the 15 nuns who make up the community. He or she must talk to the sisters through the wooden turn in the parlor wall. A 4- by 2-foot revolving cupboard, the turn is employed to receive food and other necessities and to send such items as prayer cards out of the convent.

The nuns, many of whom are young, believe they are living the life of prayer the way it is meant to be lived, and they feel no need to explain further. "No matter what you write, no one will understand," one of them said through the turn.

Less extreme and more accessible are traditional communities such as the Discalced Carmelites in Morristown, N.J. Inside this convent, however, the metal grille remains. "To some people it looks like we live in a prison," says Sister Agnes, "but the grille is not to keep people away. It is a symbol for the spirit of solitude." The 13 cloistered sisters and three postulants who make up the community leave the ground sonly to visit a doctor or dentist. Local benefactors and an extern, Sister Eliane, buy their food and perform such worldly chores as banking.

Modernization at the Morristown cloister has been more subtle than in progressive cloisters. The vows, for example, are still interpreted literally. "For me, as a subject, obedience means I do whatever my prioress tells me to do," says Sister Agnes. "It's just to be humble. We see in our Mother God's representatives."

As at most cloisters, the Mother Superior, prioress or abbess, is elected for a three-year term. When she steps down, she must ask for permissions from her successor.

Although penances are no longer practiced in many convents - "We don't feel the need to linvent difficulty in our life," says Sister Michaelene - more traditional communities still believe mortification is an integral part of contemplative life. The 38 Poor Clare Nuns of the Monastery of Our Lady of Guadalupe, who live in an enlarged old farmhouse in Roswell, N.M, continue to go barefoot throughout the year, fast regularly and nightly interrupt their sleep for an hour and a half of prayer. But perhaps the penance strangest to outsiders is "the discipline" - three times a week, the Roswell nuns whip themselves on their backs with scourges of knotted cord.

"There's a lot of misunderstanding about the discimpline," says Sister Chiara, who came to the cloister in 1968. "We do penances to unite ourselves to the passion of Christ," she explains. "It's a way of seeking reparation for our sins and the sins of the world."

The Roswell Poor Clares, who do not use surnames, have also retained the traditional clothing ceremony during which a second-year nun receives the formal habit of her order. On the morning of her clothing, the novice attends mass attired in a long white gown and veil. After the liturgy, the nun walks in procession with her sisters to the community meeting room. There, in an act symbolic of divesting herself of worldly beauty, her hair is cut short by the Mother Abbess, who then dresses the new sister in the order's heavy habit of rough brown cloth, which ahd earlier been blessed by a priest. The high point of the ceremony comes when the abbess gives the sister a new name suitable for her new life of chastity, poverty and obedience.

To explain their retention of a ceremony many cloistered sisters have abandoned, the nuns at Roswell refer to a section of a paper they and nine other communities published in 1978: "The vow (of chastity) is the nun's human and public response to a divine call uttered in the depths of her own being to show forth the brideship of the Church in her total surrender directly to God. This blessed vow is our personal bridal covenant with God."

One step beyond the cloister is the hermitage. If the call to the cloister is exceptional, the call to hermit life is rare, indeed. Sometimes a sister who desires more solitude is given a few rooms in a convent for her exclusive use. There she eats, sleeps, works and prays alone. Others, such as the Carmelite hermits in Chester, N.J., live in separate, small communities. Because the movement toward hermitages is still relatively new in the United States, statistics are difficult to come by, but it is known that the Handmaids of the Most Holy Trinity have established a hermitage at South Bend, Ind., and the Hermit Sisters of Christ in Solitude have one in Sebastopol, Calif.

The four hermit sisters in Chester live on 10 acres of land. Each nun has her own sparsely furnished 6- by 12- foot knotty-pine hermitage, built with the aid of local residents and other benefactors. A nun's only contact with the other three is during Divine Office, at Mass, during daily spiritual counselings with the Desert Mother and an hour of communal recreation, the only time when they indulge in private conversations. The hermitage nuns eat only one full meal a day, and they never know from where it will come. "God will provide" is the prevailing attitude, and they haven't gone hungry yet. Townfolk and visitors bring food and supplies on a sporadic basis. To augment such gifts, the hermits also do caligraphy and make spiritual cassette tapes.

Desert Mother Mary of Jesus, whose title reflects an ancient monastic tradition, founded the small community in 1976 after spending 26 years in the Schenectady, N.Y. Carmelite cloister, because she wanted "a life of total abandon to God without the support of a lot of human security."

But not everyone who comes to the hermitage can adjust to the severe regimen. Since its founding, half a dozen nuns have left the Chester hermitage, after what Desert Mother Mary calls "a period of discernment."

Cloistered nuns everywhere struggle with the question or what their particular role should be in today's fast changing world. High above the Israeli port of Haifa, an international community of 17 nuns practice their life of prayer on Mount Carmel, closely associated in biblical times with the lives of the prophets Elijah and Elisha. Speaking through an interpreter in a mixture of Italian and French, Mother Maria Giuseppina explained that her convent has chosen to take a middle course with the changes offered by Vatican II. "But we were not meant to remain like the nuns in Brooklyn," she said, referring to the ultra traditionalists in Crown Heights. "We are evolving toward a new equilibrium."

As they do, she said, "We will try to hold onto the purpose of this kind of order. Because Christians pray less now, there is a greater need for our work. We are intercessors between men and God - not just with our mouths, with our lives."

Sister Angela explained the particular direction of the community's prayers. "After we read Vatican II, we interpreted a new spirit." she said. "We decided to pray for all people to pray as they believe. Our main purpose is to pray for the Jewish people to be faithful to their own religion. If they are faithful, splendid things can happen. The Jews give us something in return, by letting us have this convent in Israel."

In Paris, Poor Clare Sister Ghislane, a former abbess of the community of 23 nuns which has provided temporary lodging for Vietnamese refugees outside the convent's enclosed area since 1978, was concerned about the decline in religious vocations. She feels various orders, her own included, must accept a certain responsibility for having lost touch with a fast, changing world. Nevertheless, she believes that "people understand we have found something true, solid and real. They are envious," she said in her halting English. "To live our life you must be a strong reliable person - someone who is not overly concerned with herself. I pray, and I don't mind what God does with my prayers."

The always rigid cloister entry requirements have never been more difficult. Contemplative orders are looking for evidence of geniune calling from God - not an easy thing to discern. Most orders today require psychological testing and interviews with several members of the clergy before a candidate is accepted. Two years of college, or work experience, is preferred.

"We want women, not girls," says Sister Michaelene. "You can't make choices about your life until you know what your options are."

A nun must live in the cloister for five to seven years before she makes her final vows. The sisters say that's how long it takes to determine if a vocation is real and if a woman has what it takes to live an often stark life devoid of everyday distractions.

Between 1977 and 1979, the most recent years for which comparable statistics have been compiled, 288 women left, American cloisters. By contrast, 1,887 women entered active orders and 5,694 left during that same period. For those who stay in the cloister, it is a life of extreme faith. If an active nun occasionally sees the sick healed or the poor fed, the cloistered nun has no such visible satisfaction. "It's not easy," says Sister Michaelene. "We don't see the hostilities in Lebanon ceasing because of our prayers."

The lack of concrete evidence inevitably leads to periods of near devastating doubt. "One day you come to your hour of prayer and you feel nothing," says Sister Annamae. "You begin to think, 'Am I making this all up?' Sometimes a spiritual counselor or a friend who's been through it can comfort you," she says. "But essentially you go through it alone. Once you get beyond the doubt, you're purified. You can give yourself completely to God - not in a serville sense, but as a free person."

Dealing with loneliness and the pull toward an active life is an ongoing challenge. Most communities are now quite open about discussing sexuality and the psychological implications of a celibate life, and Mother Superiors, priests and Catholic psychologists, who no longer view psychology and theology as contradictory sciences, provide sympathetic counseling.

For Sister Annamae, "The hardest thing is not to be loved exclusively by one person. We go through the gamut of emotions as much as anyone," she says, "maybe more, because we lead such a reflective life."

"I'm a red-blooded American woman," says Maryknoll Sister Rachel. "I love kids. I love men, too. I think it would be nice to have a husband. I face it. I admit it has an appeal, but I feel the pull toward religious life is stronger."

Sister Helen Werner points out that living in a cloister today does not rule out the possibility of deep platonic relationships with the men and women who visit, and with the sisters in the convent. In the past, close or "particular friendships," from the French, Amities particulieres, were forbidden. In some convents, two nuns were not allowed to be together without the presence of a third. Some sisters said the intent was to discourage exlusiveness or platonic friendships that would interfere with the primary relationship with god. Others say the unspoken reason was to prevent lesbian relationships from developing. Today, many nuns discuss the once-taboo subject quite metter-of-factly.

"We've talked about lesbianism," says Sister Michaelene. "I'm sure it happens, but it's not something we've experienced. If we did have a problem, we'd deal with it openly and sensitively. Anything that involves people living together in a small community you have to treat gently."

As to what the future holds for cloisters, Sister Michaelene thinks the contemplative life "may not be lived exactly the same way, but I think the life of prayer will continue. It's so much a part of human nature."

Despite the loneliness and doubts, most of the sisters interviewed say they are at peace in the cloister. "Like any life, it it's not for you, it can be a living hell," says Sister Marjorie. "But if the cloister is where you truly belong, it can be a beautiful life, a life of pain and sorrow balanced with peace and joy."

Many veteran nuns say their families and friends still have a hard time understanding a contemplative vocation. Sister Mary Devereux, who has been in a cloister for a quarter of century, says her mother recently asked her, "Why do you have to get up so early when you have nothing to do all day?"

Occasionally, there are surprises. "My opinion of a cloistered vocation has changed drastically," says Helen O'Hara, who first thought "What a waste," when her daughter, now Sister Carolyn, told her she was entering a Carmelite cloister. But after reading everything she could get her hands on about the order and its founder, Mrs. O'Hara says she began to understand the contemplative life "as much as a lay person can. My husband and I began to respect Carolyn's choice. She was always quiet and strong. Now I notice an inner peace in her. It's been a gift. I feel we have a powerhouse of prayer in Beacon."