Ta-mei Fa-chang (752-839) was a Chinese Ch'an master. After he got awakened under the Great master Ma-tsu Tao-i (709-788), he went to the Ta-mei mountain and resided there.
One day there was a traveling monk who got lost in the Ta-mei...
Looked at but cannot be seen - it is beneath form;
Listened to but cannot be heard - it is beneath sound;
Held but cannot be touched - it is beneath feeling;
These depthless things evade definition,
And blend into a single mystery.
In its rising there is no light,
In its falling there is no darkness,
A continuous thread beyond description,
Lining what can not occur;
Its form formless,
Its image nothing,
Its name silence;
Follow it, it has no back,
Meet it, it has no face.