It's a hard movie to watch, because it reveals some very dark episodes in the history of the church, like how entire Jewish communities in Europe were wiped out during the Crusades, and how Jews in Rome were actually walled off in a ghetto for centuries.
The title of the film, "Constantine's Sword," comes from the historical figure Constantine, a Roman emperor who converted to Christianity in the 4th century, and used the cross as a symbol of military and political conquest (as the crusaders would later do). The conversion of Constantine is a hugely important event in the history of Christianity, because it marks the point in history when the church goes from being a persecuted minority to being the official religion of the Roman Empire, and is thereafter aligned with great political power.
This collusion of religion and political power did not end with Constantine. It seems to be an ongoing issue, and one worthy of serious reflection. As James Carroll says, "Every religious person has to take responsibility for the way in which their tradition encourages intolerance, suspicion, hatred of 'the other'. And in the Christian tradition, both in relation to Muslims and Jews, we have some very clear reckoning with history to do."
Constantine's Sword is currently streaming on Netflix.