Claude Anshin Thomas is a man who used to be a soldier. That means he used to wear a soldier uniform, have a gun, and do what his bosses told him to do. But later in his life, he realized that violence hurts people and no one wins in wars.
Because he wanted to help people understand this too, he became a Buddhist monk. That means he wears orange clothes, shaves his head, and meditates a lot. He also teaches other people about Buddhism, which is a religion that talks about being kind and peaceful.
Claude Anshin Thomas wrote a book called "At Hell's Gate: A Soldier's Journey from War to Peace" where he talks about his life as a soldier and how he changed. This book helps people understand what war is really like and how harmful it can be.
So, even though he used to be a soldier, now Claude Anshin Thomas wants to help people be peaceful and happy.