Rambam - Sefer HaMitzvos: Positive Mitzvah 246: Positive Mitzvah 246

Positive Mitzvah 246: Laws of Claims
Exodus 22:8 "In every case of trespass...in which one can say: This is it"'

Ari and Izzy were playing ball on the lawn.

Suddenly, Ari felt his glove beginning to slip of his hand.

He shouted to Izzy to wait a second, but Izzy threw the ball anyway. It landed in the street sewer because Ari wasn't ready to catch it.

"Hey! I asked you to wait!" Ari yelled.

"I'm sorry, I didn't hear you," Izzy answered.

"Yes you did. I could tell! Now you've got to buy me a new ball!" Ari demanded.

"No I don't" Izzy protested.

In cases like these, where an argument arises and people disagree about who bears responsibility for a loss or damage, the Torah teaches us how to come to a fair decision.

Every created being is similar to both the sun and the moon. The sun is constant -- every day the same fiery ball rises in the sky. But the moon cycles through constant change -- one day it is whole, then it wanes until it has disappeared all together. Yet, then it is renewed, returning from nothingness.
So too, every created being must both grow and change like the moon-- and yet stay ever constant as the sun. Grow, change and constantly learn -- yet always stand firm, knowing who you are.

From: Bringing Heaven Down to Earth by Tzvi Freeman - tzvif@aol.com