Why "Western Barbarian"?
In the koan collection Mumonkon, Case 4 states:
Wakuan said, "Why has the Western Barbarian no beard?"
Momon's comment: Study should be real study, enlightenment should be real enlightenment. You should one meet this barbarian directly to be really intimate with him. But saying you are really intimate with him already divides you in two.
The "Western Barbarian" is Bodhidharma, the first Zen patriarch. He came to China from either India or central Asia and is universally depicted as having a beard.
A note on this koan says, "This is not really a meeting but a becoming. You should yourself become Bodhidharma. Then if you have a beard, Bodhidharma has a beard; if you have no beard, then neither has Bodhidharma. But can you say that in truth you are Bodhidharma?"