There's a passage in the book that I found particularly butt-kicking:
Near the Monastery there was Bukai Roshi's private house, which had been rented out for some time. When the house was vacated, I was told by Bukai Roshi, my teacher, to go and clean it.How many times do I hesitate in ways that betray my own training? What distinctions do I come up with to give myself an excuse for not diving right in?
The house as evacuated by the residents was in a terrible condition. Somehow I managed to clean the rooms, but when I came to the toilet, the condition was even worse. Besides, it happened to be a very hot day in August, and I could not help hesitating. Unknowingly, my attitude was as if about to touch something dreadful.
I was not aware that Bukai Roshi, my teacher, was behind me. Tucking up his clothes and bare footed, he pushed me away without a word, took the damp cloth from my hand and began to clean the dirty toilet. I stood aghast for a second. But the next moment I jumped at him, took back the damp cloth, and started to rub the toilet literally forgetting myself. The Roshi, looking down at me for a little while, said in a quiet tone, "With a damp cloth in your hand, you are still unable to be one with it, being disturbed by the dirty and the clean. Aren't you ashamed of your training?" I shall never forget how shameful I was at his words.