One of the most perplexing law in the bible is this one in Deuteronomy 25:11-12.
11 If two men are fighting and the wife of one of them comes to rescue her husband from his assailant, and she reaches out and seizes him by his private parts, 12 you shall cut off her hand. Show her no pity.
Of course this is only a real issue if this law is applied literally. Studies have revealed that most of the physical punishments of the OT laws can be mitigated using monetary compensation. You can check out a common and well detailed understanding I found online here and here.
But why the harshness? Loren Rosson argues that it is the issue of shame.
If you want to know other Fun Facts of the Bible...