The more you talk and think about it,
the further astray you wander from the truth.
Stop talking and thinking,
and there is nothing you will not be able to know.
To return to the root is to find meaning,
but to pursue appearances is to miss the source.
At the moment of inner enlightenment
there is a going beyond appearance and emptiness.
The changes that appear to occur in the empty world
we call real only because of our ignorance.
Do not search for the truth;
only cease to cherish opinions.
From Verses on the Faith-mind (Hsin Hsin Ming), by Seng-T’san (tr. Richard B. Clark). This is considered to be the first Chinese Zen document. You can read the full text here in a nice clean format (what appears above is only a small part). There are notes about translations and commentaries too.