If There Is No God, All Bets Are Only Bets

Olevskoy shouted, “No! Absolutely not!  I will not risk an ambush!”
“I swear to you,”  Greenwood shouted, “that there will be no ambush, and that you will have the freedom of the village afterward.”  Distant echoes, then calm again.
Olevskoy shouted, “Do you believe in God?”
Greenwood was flabbergasted.  After a moment he shouted, “No!”
“Then who are you to swear to anything?”
(from The Blue-eyed Shan by Stephen Becker)n318942