The snake asked the eagle to fly him across the desert.
The eagle refused and said, "No, if you attack me in mid-flight, I will be unable to resist."
The snake said: "I promise not to attack you. It will not do me any good. If you die, I will fall to my death if I fall from the air."
The eagle thought that the snake was right, so he agreed to the snake's request.
The eagle was flying when he suddenly felt a pain in his neck.
The snake venom gradually spread in the eagle's body, and the eagle became weaker and weaker.
When the eagle and the snake fell from the sky together, the eagle asked the snake: "Why did you bite me? Now that you have killed me, you will not survive."
The snake said: "I understand this very well, but I just can't stop myself from giving you that fatal blow, because that is the nature of snakes."