JAMES CARROLL'S new book, Constantine's Sword, is being offered as a potential watershed in Jewish-Christian relations. At the very least, it's sure to provoke controversy. Carroll, a former Catholic priest, has painstakingly examined his church's record on the Jews and found it wanting. Anti-Semitism, he believes, was woven into the fabric of Christianity almost from the beginning, so much so that nothing short of a theological revolution can purge it. Impatient with rationalizations and halfhearted apologies, he is calling for the Church to convene Vatican III to deal with the problem. And since Carroll claims that even modern, secular anti-Semitism has its roots in Christianity, his argument has important implications beyond the Christian fold.

Carroll himself is no stranger to revolution. As a young priest, he became increasingly disillusioned with the Church hierarchy's silence about the Vietnam War. He got involved with religious antiwar protesters such as the Berrigan brothers and the Reverend William Sloane Coffin, and also came under the influence of Rabbi Abraham Joshua Heschel, the Jewish theologian and peace activist. While a chaplain at Boston University, Carroll's friendships with Jews led him to try to see his church from the Jewish point of view. After leaving the priesthood, he married, raised a family, and became an acclaimed novelist. He is also the author of a memoir, American Requiem, about his relationship with his father, a devout Catholic and an Air Force general who was involved in the Vietnam War.

I met Carroll recently in the lobby of a midtown hotel for a two-hour conversation about his book. Despite his anger at the Church, he remains a practising Catholic and believes that through understanding and repentance, Christendom can still cleanse itself of the sin of anti-Semitism.