Roman Catholic leadership at present says "no" to some theoretical changes that a prominent theologian and a big-selling priest-novelist imagine as happening.

They cast their visions in different forms, one in a scholar's hypothetical scenario of a new pope's election, the other as a fictional account of an American bishop's pathbreaking innovations.If their fancies precede reality, then Roman Catholicism one of these days will officially take up ordaining women and allowing priests to marry if they choose.

That doesn't appear plausible under the present firm stance against it by Pope John Paul II and the shunning of the idea by the recently concluded Vatican synod on the priesthood.

However, surveys find majorities of American Catholics would approve it, and it comes to storied fruition in a new novel, "The Shepherd," and also flowers in the speculations of Notre Dame scholar, the Rev. Richard McBrien.

In the novel, the Rev. Joseph F. Girzone, an Albany, N. Y., priest, tells of a dutiful Midwestern priest who is named a bishop and begins a series of drastic reforms.

These include assigning married priests to evangelizing tasks, ordaining women as deacons, a first step toward the priesthood, and forming a unified ministry with Lutheran, Methodist and Episcopal bishops.

Girzone, whose previous best-selling novel, "Joshua," portrays a modern-day Jesus figure, keeps Joshua around in the new novel to advise and encourage the bishop in critical moments.

"Don't put new wine into old wineskins," Joshua advises. "Old molds are part of the past and are not sacred. New situations need new tools if the church is to help people through difficult times."

The publisher has sent copies of the novel to all the country's cardinals, archbishops and some bishops.

The fictional Bishop David Campbell meets stiff opposition, even on his own staff, but gets confidential support by many bishops, though they fear to take similar steps.

He also has the secret backing of the pope himself, who strives to hold off upset Vatican officials. On the pope's death, the reformer Campbell, by a fluke of circumstances, succeeds him.

McBrien, head of the theology department of the University of Notre Dame, envisions the reforms as coming with the conjectured election of a new pope, John XXIV, about the end of the decade.

In a syndicated column, McBrien says the imaginary new pope, named after the late reforming Pope John XXIII, immediately announces the calling of another ecumenical council, Vatican III.

Among its surmised concerns would be the church's ban on contraception, ignored by most Catholics, the shortage of priests, the requirement of priestly celibacy, and the ordination of women.

"I expect that some members of the church who were pleased with many ecclesiastical policies during the past decade will not be comfortable with the changes I have announced," the fancied new pope tells a news conference.

He nullifies the Vatican's recently promulgated "loyalty oath" and expanded "profession of faith" for priests, and announces the resignation of the Vatican's doctrinal watchdog, Cardinal Joseph Ratzinger.

"The church itself must remain acutely conscious of its own sinfulness and weakness," the new pope says. "That is why I will issue no call for discipline and obedience, unless it is good news, and unless it is obedience to the reign of God, which is a reign of justice and peace."