Unam sanctam
Okay, imagine you are in a big family where everyone has a different job to do. One person is the boss of the family, and they have the most important job of making sure everything runs smoothly.
Now, pretend that the boss of the family said something really important. They said that if anyone in the family doesn't listen to them and follow their rules, they won't be a part of the family anymore.
That's kind of like what Unam Sanctam is. It's a big rule that the leader of the Catholic Church (the Pope) made a long time ago saying that everyone in the world needs to listen to him and follow his teachings. He said that no one can be saved without being under his authority.
So, in a way, Unam Sanctam is like the boss of the Catholic family saying that everyone needs to listen to him or they can't be a part of the family.
Now, pretend that the boss of the family said something really important. They said that if anyone in the family doesn't listen to them and follow their rules, they won't be a part of the family anymore.
That's kind of like what Unam Sanctam is. It's a big rule that the leader of the Catholic Church (the Pope) made a long time ago saying that everyone in the world needs to listen to him and follow his teachings. He said that no one can be saved without being under his authority.
So, in a way, Unam Sanctam is like the boss of the Catholic family saying that everyone needs to listen to him or they can't be a part of the family.