Buddha / Buddha Nature

Clinging to both the worldly and saintly states
is the presence of passion with the absence of the Buddha-nature.
-Pai Chang

A monk asked Chan master Pai-chang:
"Who is the Buddha?"
"Who are you?" answered Pai-chang.
-Zen Humor

If you can get the point directly, 
you wear Buddha's clothing,
eat Buddha's food,
speak Buddha's language,
do what Buddha does;
that is, you are Buddha.
-Wumen

A Buddha is just someone with no concerns.
-Deshan