Deep in a quiet forest lived a marvellous deer named Ruru. His coat shone like polished gold, his eyes were like jewels, and he could speak with a gentle human voice. Because hunters would surely chase such a treasure, Ruru lived far from every village, hidden among flowering trees.
One day the river flooded, and Ruru heard a man crying for help as the water swept him along. It was a merchant's son who had lost everything. Ruru plunged into the roaring river, let the man cling to his back, and swam him safely to shore. The grateful man promised anything in return. "I ask only one thing," said Ruru. "Tell no one where I live." The man promised and went home.
Soon afterwards, the Queen of Benares dreamed of a golden deer teaching from a golden throne, and she longed to see it. The king proclaimed a rich reward — a village and ten elephants — for anyone who could find such a deer. When the merchant's son heard this, greed swallowed his promise. "I know where it lives," he said, and led the king's archers straight to the forest.
The king drew his bow, but Ruru spoke in his sweet human voice: "Wait, great king. Tell me first — who showed you my hiding place?" The king pointed to the merchant's son. Ruru sighed and said, "It is easier to pull a log from a river than to help an ungrateful man." When the king heard how Ruru had saved the very man who betrayed him, he grew angry and turned toward the traitor. But Ruru gently begged, "Forgive him, O king. Let him even keep his reward. Only let all creatures live in peace."
Amazed by such forgiveness, the king honoured Ruru, listened to his kind teachings, and ordered that no deer in his kingdom should ever be harmed again. Ruru returned to his flowering forest in peace.
When the Buddha ended this tale, he said, "In that life, the ungrateful man was Devadatta, the king was Ananda, and I myself was Ruru, the golden deer."