variety.jpgCasting bestselling author/columnist James Carroll as the teller of his own tale, Oren Jacoby’s magnificent, thought-provoking essay film “Constantine’s Sword” examines the unholy alliance between organized religion and military power. Jacoby’s focused yet peripatetic approach perfectly suits Carroll’s unique blending of historical and personal pilgrimages, as he travels to the U.S. Air Force base at Colorado Springs on the one hand and to ancient Rome on the other. Taking anti-Semitism as a paradigm for religious intolerance, Carroll sets out to ascertain where Christianity went wrong. Highly controversial, deeply felt docu bows April 18 at Gotham’s Quad and Lincoln Plaza. Full review Analyzing the church’s part in the persecution of Jews proves revelatory on many levels, particularly from the vantage point of ex-priest Carroll, whose religious convictions led him to leave the church. Early in the docu, a Jewish scholar tells Carroll that if he wants to understand anti-Semitism, he shouldn’t ask Jews. So Carroll travels to where all roads lead, Rome, tracing militant Catholicism back to the third century A.D. and the Emperor Constantine’s vision that transformed the cross into a sword, conquered Rome and converted it to Christianity.

Carroll wanders the byways of the ancient city, following the traces of the emperor’s conquest, from the huge toe fragments of Constantine’s colossal statue to the bridge over the Tiber where Christian “comforters” led Jewish women to be hanged and burned. Carroll also meets with Jews in Rome whose roots date back to the Inquisition, recounting the long, sorry history of the Sephardic Jews and the papacy.

Jacoby supplements Carroll’s private musings and casual interactions with artifacts that are absolutely integral to his subject’s quest: vintage woodcuts, ’40s newsreels, a Christian comicbook pictorializing the conversion of “the Jew that hid the Holy Cross” and a choice reproduction of the 15th-century papal edict that foreshadowed the Holocaust by walling Jews into ghettos, denying them basic rights and mandating that they wear special insignia.

What makes Carroll’s history lesson vividly immediate is that his itinerary mirrors his own inner journey. As Carroll puts it, with a mother named Mary, a father named Joseph, and the initials “JC,” God was practically part of the family. When Carroll’s father, a high-ranking Air Force general, was stationed in Germany, his mother took him to sites commemorating St. Helena, Constantine’s German-born mother. In the 1960s, as contemporaneous footage attests, Carroll was not the only priest to oppose the war in Vietnam, but he may have been the only one to demonstrate beneath his father’s window.

Continuing his odyssey to discover the “things people are doing in the name of God,” Carroll motors to another idealistic beacon of his childhood — the Air Force Academy, here under the proselytizing spell of Ted Haggard in his pre-scandal, evangelical heyday. It may be a toss-up as to which is more frightening, the hooded figures of the Inquisition or the fanatical grin with which Haggard proclaims his Bush-sanctioned right to infiltrate the military and convert its members.

Tech credits are solid, including stellar voiceovers by Liev Schreiber, Phillip Bosco, Natasha Richardson and Eli Wallach.