Practice and more practice

One day, Po Chü-I (a famous poet and official of the T'ang Dynasty), passing along a road, saw a Zen monk seated on a tree branch preaching the Dharma. The dialogue below ensued:

Po Chü-I: "Old man, what are you doing in that tree, in such a precarious position? One misstep, and you will fall to your death!"

Monk: "I dare say, Your Lordship, that your own position is even more precarious. If I make a misstep, I alone may be killed; if you, as a high official, make a misstep, it can cost the lives of thousands."

Po Chü-I: "Not a bad reply. I'll tell you what. If you can explain the essence of Buddhism to me in one sentence, I'll become your disciple. Otherwise, we will go our separate ways, never to meet again."

Monk: "What an easy question! Listen! The essence of Buddhism is to do no evil, do what is good, and keep your Mind pure."

Po Chü-I: "Is that all there is to it? Even a child of three realizes that!"

Monk: "True, a child of three may realize it, but it is not sure that a man of eighty can practice it!"