One day, Ananda asked Mahakasyapa, "My elder brother in the Dharma, when the World Honored One transmitted his golden embroidered winter robe to you did he pass on anything else?"
Mahakasyapa called out, "Ananda!"
Ananda responded, "Yes, Master?"
Mahakasyapa said, ""Chop down the flag pole in front of your temple gate!"
In other words, the lesson was over after their brief exchange. Beyond "Ananda!" and "Yes, Master?," there was no need for more words.
"Ananda!," called out Mahakasyapa - direct and penetrating.
"Yes, Master?" replied Ananda, like an echo in the valley, a spark flying off from a flint. But if a single thought had risen, all would have been lost in intellect.
When Mahakasyapa said to chop down the flag pole, "lesson over," Ananda realized that Mahakasyapa was not calling Ananda's name and Ananda's replying was not an answer. Intimate and immediate, the valley does not know the echo.
Although he had a complete understanding and knowledge of the Buddha's teaching, Ananda still felt that there was an "Ananda" to somehow "possess" the Buddha's nature, that indeed there was even anything to receive. This delusion kept him from fully grasping the meaning of the Buddha's truth. When Mahakasyapa calls out to him, "Ananda!" and Ananda instinctively replies without a single thought arising, Mahakasyapa says, in effect, "That's it!" At that moment, Ananda recognized his true self and realized enlightenment.
To say any more about it would be to miss the point.