"Suppose one morning you're walking to work and a man yells abuse and insults at you from across the street. As soon as you hear this abuse, your mind changes from its usual state. You don't feel so good; you feel angry and hurt. That man walks around abusing you night and day. Whenever you hear the abuse, you get angry, and even when you return home, you're still angry because you feel vindictive, you want to get even.
"A few days later another man comes to your house and calls out, 'Hey! That man who abused you the other day, he's mad, he's crazy! Has been that way for years! He abuses everybody. No one takes any notice of anything he says.' As soon as you hear this you are suddenly relieved. That anger and hurt pent up within you all these days melts away completely. Why? Because now you know the truth of the matter. Before, you thought that man was normal, so you were angry with him. Your misunderstanding caused you to suffer. As soon as you found out the truth, everything changed: 'Oh, he's mad! That explains everything!'
"Now that you understand, you feel fine. Now you can let go. If you don't know the truth, you cling right there. When you still thought that man who abused you was normal, you could have killed him. But when you found out the truth, you felt much better. This is knowledge of the truth."