THOUGH NOT widely known outside the region, Will D. Campbell has been a significant and controversial figure in the postwar South. During the most tumultuous years of the civil rights struggle, he served as southern field representative for the National Council of Churches; more recently he has been director of the Committee of Southern Churchmen. In both positions he has been a passionate, outspoken advocate of black rights and of an alliance between poor blacks and whites--positions that have won him ardent admirers among civil rights activists and equally ardent detractors among the white establishment, especially that of the Baptist Church of which he is a renegade minister.

Campbell described his life as a radical, neo-populist churchman in his memoir, Brother to a Dragonfly, which was published in 1977. With humor and occasional bursts of anger, he recalled his metamorphosis from a reflexive acceptance of his native Mississippi's racial attitudes to an awareness of injustice and a commitment to spend his life fighting it. He also described his curious relationship with organized religion; he is an ordained minister who for the most part holds churches in contempt, finding them rigid, intolerant and exclusive, and who has made great sport out of tweaking the highly sensitive noses of his fellow Southern Baptists.

It is this view of religion that permeates The Glad River, Campbell's first novel. As an expression of Campbell's belief in a universal church to which all are welcome as members, it is powerful and moving; it glows with commitment and conviction from the first page to the last. But as a work of fiction it is considerably less successful; it has no clear shape or internal logic, its characters never stop carrying the thematic signboards that Campbell has assigned them, and there is entirely too much uninterrupted talk. Campbell is a fine prose stylist, so the novel moves along smoothly enough; but he never arouses much interest in the people whose stories he tells.

There are three of them, bearing the somewhat unlikely names of Doops Momber, Kingston Smylie and Fordache Arceneau. They meet in 1942 at Camp Polk in Louisiana, where they are in basic training. They are young Southerners who for different reasons are outcasts: Doops has steadfastly refused baptism into the Baptist Church of which his parents are loyal members, Kingston has a strain of black blood, and Fordache is a Louisiana Cajun who speaks little English and comes from a primitive, isolated settlement. They establish an alliance that they think of as a "neighborhood," a "community." Doops says: "Maybe the difference between a community and a country is that a community has a soul and a country doesn't. Because God created the community and man created the country."

They are sent to the Pacific, where after a stay at New Caledonia (an Army outpost that Campbell describes with flair and detail) they move on to Guadalcanal. There they are separated when a landmine explodes; Doops finds himself face to face with an exhausted, ailing Japanese man whom he refuses to kill. Eventually the two work out a rudimentary form of communication through which Doops discovers that the man is not a soldier: "I've done taken a preacher prisoner . . . . We got us a holy man."

When he is at last found by the Americans and taken to a hospital, Doops retreats completely into himself, and begins writing a story about the Anabaptists, the 16th-century Dutch who were persecuted for their unconventional beliefs: "They did not believe in baptizing infants. And because they did not believe in taking human life, would not go to war. They did not believe in the death penalty, so they were not allowed to serve on juries. They believed that the Church and the State should be completely separate. They would not swear, because they understood the scripture to forbid it. They led simple lives, did not engage in politics. And some of them, a few of them, practiced community of goods."

This description is given several years after the war when Doops is a witness in the trial of Fordache, who is accused of raping a 20-year-old Mississippi woman with whom he had fallen in love. With McCarthyism heavy in the air, the trial has less to do with the actual charges-- Fordache is obviously innocent--than with the religious and social beliefs to which these three latter-day Anabaptists have committed themselves. Fordache is convicted and executed, but before his death Doops goes to him and asks to be baptized; thus he is received, of his own free will, into the universal church. He is a witness at Fordache's execution, and in his mind hears his friend speak:

"What he could hear was like words from a record in a doll's belly. What he could see was not the words themselves but depictions of what they said. I am helpless and you are helpless. I love you and you love me. I love life and I am about to die. You can do nothing, and I can do nothing. My life is ending. There is a pool. There is a river, the streams whereof shall make glad the city of God, the holy place of the tabernacles of the most High. The heathen raged, the kingdoms were moved; he uttered his voice, the earth melted. The Lord of hosts is with us; the God of Jacob is our refuge. There is a river. There is a pool. Selah."

The parallels to the story of Christ are, alas, all too transparent; the story is never really permitted to assume a life of its own. Like another recent novel about religious commitment, Larry Woiwode's Poppa John, The Glad River is so preoccupied with its messages that it never finds time to become a novel. This leaves the reader in an odd and uncomfortable position: on the one hand admiring the author for what he believes and the depth of his belief, yet on the other hand vexed that he has been unable to transform that belief into a work of art.

The problem may well be that Campbell is so intent on presenting what is essentially a sermon--so determined to use the novel as a forum for expressing and advancing his views--that he simply loses sight of the novelist's obligation to involve the reader in his characters and their lives. Whatever the case, Will Campbell is an extraordinary human being who has done noble work, and who earlier wrote a fine memoir, but he is not a novelist.