By morning, the snow had stopped but the wind had carried loose flakes across the roads and driveways, turning them into slick sheets of ice. Driving would be difficult, but everything is white and beautiful and a wonder to behold. It appears almost as if Odin himself had breathed over the land, leaving his exhalation of frost and ice on everything.
Nangaku said, “I am polishing the tile to make it into a Mirror.”
We should clarify the meaning of these words. In “polishing the tile to make a mirror,” the dharma of all the Buddhist teachings are present and the dharma of the entire realized Universe is present. "Polishing the tile to make a mirror" is never an empty pretense.
Even though a tile is a tile and a mirror is a mirror, keep in mind that when we are striving to clarify the truth of polishing, the practice possesses a limitless abundance of distinguishing features.
Both the Ancient Mirror and the Bright Mirror are made by polishing a tile. If we do not know that all such mirrors come from polishing a tile, we have failed to grasp the patriarchs' expression of truth, we have not heard and grasped the patriarchs' words, and we have not experienced the patriarchs' exhalations.
(adapted from Shobogenzo Zazenshin by Zen Master Dogen, 1242)