Back in the 1920’s, when I was maybe eight or ten years old, and living in New Jersey where the winters are cold, we had a furnace in our house that burned coal. It was a big event on the block when the coal truck pulled up and all this stuff poured down the coal shute into the coal bin. I learned that there were two kinds of coal that showed up in the coal bin: one was called anthracite or hard coal, and the other was lignite, soft coal. My father told me about the difference in the way those two kinds of coal burned. Anthracite burns cleanly, leaving little ash. Lignite leaves lots of ash. When we burned lignite, the cellar became covered with soot and some of it got upstairs into the living room. Mother had something to say about that, I remember. At night my father would bank the fire, and I learned to do this too. Banking the fire means covering it with a thin layer of coal, and then shutting down the oxygen vent to the furnace so that the fire stays in slow-burning state. Overnight the house becomes cold, and so in the morning the fire must be stirred up and the oxygen vent opened; then the furnace can heat up the house.
What does all this have to do with our practice? Practice is about breaking our exclusive identification with ourselves. This process has sometimes been called purifying the mind. To “purify the mind” doesn’t mean that you become holy or other than you are; it means to strip away that which keeps a person—or a furnace—from functioning best. The furnace functions best with hard coal. But unfortunately what we’re full of is soft coal. There’s a saying in the Bible: “He is like a refiner’s fire.” It’s a common analogy, found in other religions as well. To sit through sesshin is to be in the middle of a refining fire. Eido Roshi said once, “This zendo is not a peaceful haven, but a furnace room for the combustion of our egoistic delusions.” A zendo is not a place for bliss and relaxation, but a furnace room for the combustion of our egoistic delusions. What tools do we need to use? Only one. We’ve all heard of it, yet we use it very seldom. It’s called attention.
-Charlotte Joko Beck
From Everyday Zen, pages 31-32