The teaching in my school (Kwam Um) is very straightforward. There are some things we hear again and again — like “The dog is barking. Woof! Woof!” — which seemed quite comical the first time I heard them. By their very simplicity, they made no sense to me.
Sometimes I repeat some of these things to my friend who practices in the Tibetan school, and she says that Zen seems so obscure — it is too difficult for her. Well, I never argue with that. Many of these things seemed opaque or obscure to me too (and some still do).
Your mind is clear like space, which means it is clear like a mirror. Everything is reflected just as it is: when red comes, red appears in the mirror; when white comes, white. The sky is blue. The tree is green. A dog is barking, “Woof! Woof!” Sugar is sweet. When you see something, that is your true nature. When you hear, smell, taste, touch, and think, that is also your true nature, your original substance and Buddha. Everything is already the truth.
That teaching came from Zen Master Seung Sahn, in The Compass of Zen (p. 261).