Harry Potter and the Sorcerer’s Stone;Dumbledore: Harry, do you know why Professor Quirrell couldn’t bear to have you touch him?
[Harry shakes his head]
Dumbledore: It was because of your mother. She sacrificed herself for you, and that kind of act leaves a mark.
[Harry reaches up to touch his scar]
Dumbledore: No, no. This kind of mark cannot be seen. It lives in your very skin.
Harry: What is it?
Dumbledore: Love, Harry. Love.