"Followers of the Way, you take the words that come out of the mouths of a bunch of old teachers to be a description of the true Way. You think, 'This is a most wonderful teacher and friend. I have only the mind of a common mortal, I would never dare to try to fathom such venerableness.' Blind idiots! You go through life with this kind of understanding, betraying your own two eyes, cringing and faltering like a donkey on an icy road, saying, 'I would never dare speak ill of such a good friend, I'd be afraid of making mouth karma!'
"Followers of the Way, the really good friend is someone who dares speak ill of the Buddha, speak ill of the patriarchs, pass judgment on anyone in the world, throw away the Tripitaka, revile those little children, and in the midst of opposition and assent search out the real person. So for the past twelve years, though I've looked for this thing called karma, I've never found so much as a particle of it the size of a mustard seed.
"Those Ch'an masters who are as timid as a new bride are afraid they might be expelled from the monastery or deprived of their meal of rice, worrying and fretting. But from times past the real teachers, wherever they went, were never listened to and were always driven out--that's how you know they were men of worth. If everybody approves of you wherever you go, what use can you be? Hence the saying, let the lion give one roar and the brains of the little foxes will split open.”
excerpt from "The Zen Teachings of Master Lin-Chi" translated by Burton Watson (see http://www.allspirit.co.uk/rinzai.html