“Koan practice means pulling the rug out from under your thinking. When you do this, it becomes starkly clear that thinking has nothing to do with your true nature. Your true nature is before thinking. Kong-ans can't be approached with your thinking, they must be approached with your confidence. This means asking, "Do I believe in myself? Can I trust life's experience this very moment?" We may think that confidence is an encyclopedia salesperson ringing a doorbell, confident in what she's selling. This isn't confidence, this is selling yourself something, selling yourself an idea and making it so strong, you can't be open to the universe. True confidence is completely accepting your not-knowing. It's accepting that no one knows and understanding that this is okay. When you do this, your universe becomes bigger. But when you take one idea, formulate something, and become attached to it, your universe shrinks. So let your universe become large. Let your sitting be without boundaries, and a good answer will appear all by itself.”
—Zen Master Bon Haeng (Mark Houghton), a Zen Master in the Kwan Um School (Dharma Zen Center’s greater organization)
The full Teaching can be found at:
https://kwanumzen.org/teaching-library/2002/04/01/let-your-universe-become-large