Everywhere one looks this holiday season, the church and the state are mixing and mingling forcefully if not always comfortably.

The two reverends -- Jesse L. Jackson and Marion G. (Pat) Robertson -- are roiling the waters of the Democratic and Republican parties. And everywhere politicians are having to adjust to the new moral and religious commentary on their work, much of it coming from ministers in their midst.

It's a healthy phenomenon, in the eyes of this secular reporter-critic, and not the menace some see. The clerics often speak uncomfortable truths to the mighty. The other day, for example, as the Senate was trying to finish up its work for the year, Senate Chaplain Richard C. Halverson prayed that ''as this final week of work begins, cleanse us and renew a right spirit within us,'' and then offered this unblinking assessment of what he had observed:

''This past week was exhausting, physically, mentally, emotionally. Despite very hard work, there seemed to be little satisfaction with the legislation. There has been much second-guessing over the weekend. Some have regretted the position they took -- some whose action on the floor was different from brave words in the cloakroom, some who were intimidated and lacked courage to obey their conscience. Father, relieve the weariness, the discouragement, the feeling of disintegration and impotence. . . ."

Senate Majority Leader Robert C. Byrd observed pointedly, ''I am not sure that my perception of the aftermath of the Senate's work of this past week comports with the perception that the chaplain apparently had.'' But you can't fire the chaplain.

Still, many are uncomfortable with the ministerial voice in politics. As James M. Wall, editor of The Christian Century, wrote in his magazine earlier this month, ''a little goes a long way'' when it comes to religion in politics. ''Our pluralistic culture appears nervous over the prospect of a religiously committed leader assuming power. . . . Surface religion is rewarded but deep commitment is suspect. . . . In 1960 Protestants didn't want John Kennedy taking orders from the pope. In 1988 the papacy is no longer a threat -- but God is.''

Wall's ironic comments are borne out by the deep public concern I have heard in interviews all year about the prospect that either Jackson or Robertson would become president. The criticism of Jackson blends negative feelings about his personality, his race, his perceived political radicalism and his vocation as a preacher. But the equally vehement antagonism to Robertson is clearly an aversion to his religion. ''God help us,'' a voter in the Pittsburgh suburbs told me a couple of weeks ago. ''He'd probably have the women in veils.''

The exaggerated fear embedded in his implicit comparison of Robertson to the Ayatollah Khomeini carries over to an even more hysterical castigation of Robertson's followers. A few weeks back, Wall's excellent magazine published a piece by California free-lance writer Timothy B. Lynch, who said: ''Having engaged in political combat with the Religious Right, I can attest to its moralistic, zealous and even intolerant approach to politics, and its tendency to label opponents as the embodiment of evil. But its followers are sincerely motivated and have every right -- perhaps even an obligation -- to participate in the political process.''

Lynch is correct. The surge of religious fervor into the political arena is a recurrent phenomenon, not a new ''menace.'' We have seen it before in the church-based movements for abolition, for temperance, for disarmament and for civil rights.

It fits into -- and need not threaten -- our pluralistic culture because it is far from one-dimensional in itself. As Lynch reminds us, ''In reality . . . many Jackson supporters resemble Robertson's followers -- churchgoing citizens of moderate means who long for the triumph of good over evil and for the realization of justice in our time. While the Jackson candidacy is a far cry from Robertson's, one need only think back to Jimmy Carter's 1976 campaign -- which appealed to people who have now divided to support Jackson or Robertson -- to realize that this constituency is not monolithically liberal or conservative.''

His point is borne out by a survey of the board members of the National Association of Evangelicals, which showed Robertson running fourth among the six Republican contenders.

A similar diversity can be found in the religious groups playing the political game. Reporters recently received a guidebook, ''Religion and Public Affairs,'' written by Phyllis Zagano and published by the Rockford Institute, listing 168 different church-based or religious-denominated groups working in the political arena.

The range is awesome, going from such specialized outfits as Affirmation, a voice for ''gay and lesbian Mormons,'' to such giants as the American Jewish Congress, the Lutheran Office for Governmental Affairs and the U.S. Catholic Conference.

The endless variety is also reassuring, for it reflects the diversity in our society. We are wrong to feel threatened whenever some man or movement of strong religious faith appears on the political scene.