The body is the bodhi tree
The mind is like a bright mirror’s stand.
At all times we must strive to polish it
And must not let dust collect.
- Hongren
Bodhi originally has no tree
The bright mirror also has no stand
Fundamentally there is not a single thing
Where could dust arise?
-Shenxiu
From what I remember (I am not going to look it up) this poem is actually two poems which were written when a new abbot was required for a monastery and the monks were required to write a verse to prove themselves worthy of the post. The first one was written by the head monk (the natural successor).