The core of Chan/Zen is found in the intuitive understanding of beyond the beyond.
This is expressed in many teachings. In the Heart Sutra it’s expressed in the first few lines: Form is emptiness, emptiness is form. Also in the mantra at the end: “Gate gate paragate, Bodhi Svaha.”
This is translated by some as: Gone, gone all the way to the other sure; the entire sangha gone beyond the beyond, enlightenment, hallelujah. Others have add gone beyond all concepts, gone beyond the cycle of birth and death, gone beyond the boundaries of space and time.
It’s expressed in the Diamond Sutra: “Anyone who believes in a personality, a being, a self, a lifespan or a soul is not a Bodhisattva.”
Hui-neng, the sixth Chinese patriarch, expressed it as from the first not a thing exists.
Some people think that Zen is something you practice to deal with difficulties in this life. But Zen is much more, much deeper than that.
Some people point to the so called crazy clouds in history and use them to justify ignoring the precepts and doing whatever they want. But these people have left the path of Buddhism. To truyl practice Zen you must constantly work on the precepts and the teachings of the Sutras.