The last line, "The exquisite dharma-dance of the birth of a buddha." All buddhas come to life the same way: by realizing the nature of the self, experiencing the death of the ego, the death of a self that separates us from everything else.
Then it goes on to say,"What was it that was realized?" What did Xuefeng realize to make him cry out "Today Turtle Mountain has attained the Way!"?
The first line says, "Xuefeng and Yantou accompanied one another visiting Zen masters." The footnote says, "Complications are sure to arise." This is no casual journey. Indeed, it was a pivotal journey in the life of Xuefeng and an intentional journey as far as Deshan and Yantou are concerned.
It continues, "When they arrived at Turtle Mountain, they were snowed in and forced to stop. Yantou spent his time sleeping every day." The footnote says, "If tired, sleep; when hungry, eat." The next line says, "But Xuefeng sat earnestly in meditation," and the footnote says, "What is it that he's seeking?" Often when the teachings express that there's nothing to find, people immediately think that this is a put-down of zazen and a justification of anything-goes Zen—nothing could be further from the truth.
The koan continues, "One day, Xuefeng called out, 'Dharma brother, wake up!'" The footnote says, "The leper wants to drag his companion along." Xuefeng wanted to pull Yantou into it.
Yantou said, "What's the matter?" The footnote says, "I was dreaming a dream within a dream. Why do you bother me?"
Xuefeng replied, "This has been a pity throughout my life. When I travelled with another monk, he only upset me. Now, I'm travelling with you here, and all you do is sleep." Footnote says, "This puppy's got some problems; everything upsets him."
Yantou shouted, "Go to bed! You meditate all the time. But it's as if you are in a far away village inside the land of some remote place." Footnote says, "If it's not happening here, it's not zazen." That's the key. So many of us take the posture of a buddha, go through the ritual of meditation, but are we really doing zazen? If it's not happening here—in other words, if you're not in this moment—then it's not zazen. It's thinking. It's worrying about the future. It's worrying about the past. And it's missing the moment, which is our life.