It is not easy to meet with wisdom and awaken to reality. I will show you a way in, listen! In hearing, there is no hearing. Hearing does not depend on hearing. Hearing is not born and it can never die. When sound arises, hearing does not create it. When sound diminishes, it is not extinguished by hearing. Nor is the nature of hearing created by the arising or diminishing of sound. Just realize that hearing is unborn and undying. Hearing does not come and go. How can you realize the wisdom of this? Listen!
~Louie Wing, ~The Flatbed Sutra of Louie Wing
It is simply illumination of the mind in seeing forms, and realization of the truth in hearing sounds. The mind described as “the mind to be illuminated” may be the mind of Buddha. The truth to be illuminated may be the truth of Buddha. In the truth of Buddha and in the house of Buddha, we just illuminate the mind by seeing forms and realize the truth by hearing sounds; there is nothing else at all.
~Dogen, Shobogenzo 28 (The Secret Shobogenzo), Butsu-kojo-no-ji, Gudo Nishijima & Mike Cross