Imagine how terrified humans were to be accused by a pope or an imam of offending a god and knowing that the pope or the imam had the final say in the issue!
There were no higher courts to which people could go for help.
John Calvin ordered the death of a seven-year-old child for slapping his parents, and the crowd honored that wretched crime as the will of a god.
They traveled in packs comparible to rabid dogs, singing the praises of one or another god as they went, and all the while they preached from the "good" books how to be holy.
It is catholic propaganda to claim the Protestants were just as bad. evidenced by the fact that since the end of the holy roman empire there is no more inquisition. The Protestants were often just defending themselves from Rome's empire.
Rome's holy wars do continue only under another guise otherwise we would all know who the enemy is. Since the HRE fell she continues as the world revolution.