Aesop, Fables I:
“The eagle and the fox, having become friends, decided to live near each other and made this casual acquaintance a confirmation of their friendship. The eagle ascended a very large tree, where it laid its eggs. The fox gave birth near a bush below.
Once, when the fox left in search of food, the eagle, who was also hungry, flew down to the fox’s den and seizing its babies, dined upon them among its own young. When the fox returned and saw what had been done, it did not grieve so much for the death of its young as it did for the prospect of revenge. Being a land animal, it could not pursue a winged one. And so, standing far away, it did the only thing which is left to those lacking power and strength – it called curses down upon its enemy. But it happened that it did not have to put off the punishment of this violation to friendship for long. For, when some people were sacrificing a goat upon the field, he set upon the altar and drew from it some of the burning innards. When it was brought home, a strong wind began to blow and created a bright fire from an old and tenuous stalk. On that account, the eagle’s young were burned – for their winds were still unformed – and they fell to the ground. The fox then ran to the young and ate them in front of the eagle’s eyes.
The fable makes clear that those who betray their friendship, though they may flee the revenge against their wrongdoings because of the opposite party’s weakness, will yet not evade the punishment sent by god.”