Master Mahan is a character mentioned in the Book of Mormon, which is a religious book followed by members of the Church of Jesus Christ of Latter-day Saints. He is not a real person, but rather a character in a story.
In the story, Master Mahan is a person who uses violence and evil to get what he wants. He is the opposite of Jesus Christ, who taught to love and be kind to others.
When people talk about Master Mahan, they are usually referring to the idea that it is wrong to use violence and harm others to get what you want. Instead, they believe that we should act in a way that follows Jesus's teachings and be kind to one another.
In summary, Master Mahan is a character in a story that teaches a lesson about how to treat others. We should try to be like Jesus and be kind, instead of using violence and evil to get what we want like Master Mahan.