Flagellants were men and women who practiced physical forms of self-punishment in order to purge themselves and the world of sin. People have been practicing self-punishment for centuries, denying themselves even the most minimal comforts in order to appease various religious rites. And, in the chaos of the Middle Ages, the flagellant movement gained particularly noticeable popularity among the pious.
Most people know about flagellants from Dan Brown books and medieval lore, but the actual slaps and cries of medieval flagellation are deeply rooted in the need to please God, make disease and hardships go away, and stave off the impending end of the world.
The Catholic Church has a long history of self-punishment and asceticism, and self-flagellation was just one of the many acceptable forms of penance. In addition to atoning for personal sins, there was a belief during the Middle Ages that economic and social struggles were a sign that God was unhappy and mankind needed to make amends.
Self-flagellation was used as a way to bleed and experience pain for God. It was also thought of as a way to control emotions, prevent temptation, and discipline one's self. After all, the sins of the flesh needed to be met with the appropriate punishment of the flesh if there was any hope of receiving forgiveness.
Sometimes flagellants whipped themselves so hard and successfully, that their blood would be flung out into the crowd. Accounts of people then taking the blood and rubbing it in their eyes speak to the value of the sacrifice. It was thought that the blood of a flagellant had miraculous properties.
As flagellants made their way from town to town, they walked around without shirts on, but wore masks or hoods to hide their faces. This was particularly helpful for women, who were showing much more skin than would have usually been acceptable in a public setting.
Given that flagellants slept on straw each night, this must have made for a less-than-restful experience, which was exactly the point; however, the more they suffered, the more they mitigated evil in the world.
Flagellants would walk for hours every day, moving from town to town. They had bare feet, few clothes, and beat themselves and each other three times at each town along the way. The entire procession lasted exactly 33 1/2 days, but why?
According to the flagellants, Christ was angry at mankind and would destroy the world in 33 days. But because the Virgin Mary was able to buy humanity more time, each procession would walk for 33 and 1/2 days, bleeding and showing devotion to God in hopes of preventing the end of the world.
Other versions of the story theorize that flagellants marched for 33 1/2 days in order to honor each year that Christ lived on Earth.