This week the lesson will be about Gargoyles!

Gargoyles can often be found on churches. In their resting state they're like statues but when evil approaches, they come to life.
They only come alive to ward off evil, that's why evil beings can't enter churches with gargoyles on it.

We saw the gargoyles in action in the episode "Charmed Again" (season 4). Piper and Phoebe were trying to convince Paige that she's a witch and their sister in the church where Patty and Sam left baby Paige. The Source took control over Shane's body who was Paige's boyfriend at that time. He tried to enter the church to convince Paige to join evil but he couldn't enter because of the gargoyles.