The Vatican has issued new rules for releasing disatisfied Roman Catholic priests from their vows of celibacy, which may reduce the number of men permitted to leave the preisthood to marry.

When he assumed office two years ago, Pope John Paul II stopped reviewing applications for priests to be "laicized," or allowed to become Roman Catholic laymen, until the situation could be studied and new procedures drawn up. Under Roman Catholic doctrine, a mane who leaves the priesthood is automatically excommunicated unless he has received the Vatican's approval.

During the 15-year pontificate of John Paul's predecessor, Pope Paul VI, more than 32,000 requests for laicization were received and al but about 1,000 were granted. Some 12,000 came from American preists alone during the last 12 years. An estimated 4,000 requests have piled up during John Paul's two-year moratorium.

The new directives, which were sent "sub secreto" -- under secrecy -- to bishops and heads of religious orders on Oct. 14, seem to promise that in the future fewer priests will be "dispensed" from their vows so that they may marry and remain in the church in good standing.

According to experts in canon law, the new procedures themselves involve few policy changes. But an accompanying three-page letter, signed by the heads of the Sacred Congregation for the Doctrine of the Faith, which handles the laicization process, reflects the often-stated views of the present pope that the celibacy vows a priest takes when he is ordained represent a life-time commitment.

The letter suggest only two sets of circumstances in which priest could be released from their vows of celibacy:

Older priests who may have married and "left the priestly life for a long period of time and who hope to remedy a state of affairs which they are not able to quit."

Younger men who "should not have received priestly ordination," either because they lacked the necessary maturity or sense of responsibility to carry out the tasks of a priest, or because the superiors who approved their ordination were unable to judge "whether the candidate really was suited for continuously leading a life of celibaccy dedicated to God."

The letter emphasizes that priest should not think they have "a right" to be released from their vows. On the contrary, it said, the priest must recognize that "despite the serious difficulties which . . . can happen to him in this life, Christ and the people of God expect the priest to observe the fidelity which he had promised them."

The message from the Sacred Congregation reminds the church's bishops or "just how great a value is to be set on priestly celibacy" by the pontiff. It quotes from the pope's Holy Week message to priests in 1979, in which he stated that by ordination, the priest "binds himself to the obligation of celibacy with full awareness and freedom . . . after having spent many years in preparation and after having given careful deliberation to and much prayer over this matter."

Some canon lawyers who have seen the new document predicted that fewer requests for laicization would be approved now, but others adopted a wait-and-see attitude. The Rev. James Provost, who teaches canon law at Catholic University, pointed out that while the pope is a strict constructionist on doctrine, he is also "a man who is touched by individual cases," who would be able to temper his "strong policy" with "human compassion."

The pope's repeated statements on priestly celibacy, in Provist's view, reflect the pontiff's attempt to encourage an attitude that the priesthood is a permanent vocation. "It's not an in-and-out affair," Provost said, "not like you can quit and go to work for General Motors tomorrow."

Several months ago, the Vatican began processing its backlog of laicization requests, even before the new norms were distributed. According to a dispatch from the church-owned National Catholic News Service, "the majority" of the requests are being granted but "a more substantial minority" was being denied than during the reign of Pope Paul VI.

Frank McGrath, who head CORPUS, a Chicago-based association of resigned priests, estimated that one-fourth of priests who leave the priesthood to marry never apply for laicization because "it's phony . . . the whole thing is a legal fiction. You can't be laicized once you are ordained. Priesthood is forever."

Even for a man who has gone through the laicization process, said McGrath, "Nobody denies he is still a priest . . . not even the pope will deny that. In an emergency, he can still function as a priest."

McGrath maintained that the "primary motivation" for requesting laicization is "legalistic, or to keep the family happy, or for the job; sometimes you have to do it because of your -- or your wife's -- job."

For a growing number of inactive priests -- CORPUS refuses to call them former priests -- even excommunication poses no threat, McGrath said. "What does it mean?" he said. "You can't be thrown out if you won't leave."