A few gems from my Zen sermons:
"seeing is not the ultimate seeing; seeing not seeing is seeing.
Knowing is not knowing untill you know what it means not to know.
You won't understand understanding without understanding not understanding."
" If you use your mind to study reality, you won’t understand either your mind or reality. If you study reality without using your mind, you’ll understand both. Those who don’t understand don’t understand understanding. And those who understand, understand not understanding. People capable of true vision know that the mind is empty. They transcend both understanding and not understanding. The absence of both understanding and not understanding is true understanding Seen with true vision, form isn’t simply form, because form depends on mind. And mind isn’t simply mind, because mind depends on form. Mind and form create and negate each other. That which exists exists in relation to that which doesn’t exist. And that which doesn’t exist doesn’t exist in relation to that which exists. This is true vision. By means of such vision nothing is seen and nothing is not seen. Such vision reaches throughout the ten directions without seeing: because nothing is seen; because not seeing is seen; because seeing isn’t seeing. What mortals see are delusions. True vision is detached from seeing. The mind and the world are opposites, and vision arises where they meet. When your mind doesn’t stir inside, the world doesn’t arise outside. When the world and the mind are both transparent, this is true vision. And such understanding is true understanding."
"To see nothing is to perceive the Way, and to understand nothing is to know the Dharma, because seeing is neither seeing nor not seeing and because understanding is neither understanding nor not understanding. Seeing without seeing is true vision. Understanding without understanding is true understanding."
"Using the mind to look for reality is a delusion."
"Not to let go of wisdom is stupidity. When the mind doesn’t exist, understanding and not understanding are both true. When the mind exists, understanding and not understanding are both false."
"To see form but not be corrupted by form or to hear sound but not to be corrupted by sound is liberation. Eyes that aren’t attached to form are the gates of Zen. In short, those who perceive the existence and nature of phenomena and remain unattached are liberated. Those who perceive the external appearance of phenomena are at their mercy. Not to be subject to afflictions is what’s meant by liberation. There’s no other liberation. When you know how to look at form, form doesn’t give rise to mind and mind doesn’t give rise to form. Form and mind are both pure."
"When the mind reaches nirvana, you don’t see nirvana, because the mind is nirvana. If you see nirvana somewhere outside the mind, you’re deluding yourself."