Something that happened before i was 12

When I was around 7 I witnessed a certain even that still to this day plays in a loop in my head. At the time we lived in Saint Charles in some town homes. The place was very nice. We had a public pool and a indoor recreational center that people could rent out and host parties and other events. It was a beautiful summer day and my sister and I were walking around that area and saw a big group of people walking in. It seemed to be open to the public, so having nothing to do at the time we ran back home to grab our father and ask him to take us to see what was going on. We went inside and there seemed to be a play going on. Nobody said anything to us and we just sat down with the rest of the people. A man in a black robe covering his face comes out. He puts both his hands on a stake that has been placed in the center of the stage. Then another person comes out with a whip and proceeds to whip this man. He begins to scream in pain. People just stood and watched. Me and my father look at each other and left immediately, never knowing the reason why that just happened. This event didn't change who I was as a person but yet still has some meaning to me because that day i realized that life can be very weird. I picked this expirence in my life because it was one of the first things that happend to me that i could not really explain. It left a long lasting image in my head that I can still see to this day.