Isan

He was as great a master as one can be, but has left behind him neither great scriptures nor great commentaries. Isan functioned exactly as Buddha had said an authentic master would -- to disappear in the blue sky like a bird, leaving no footprints.

Isan was very polite. Naturally his politeness would affect whatever happened around him. He was a very humble person, never tried to convert anybody, but on the contrary slipped deep down into the forest, so nobody came to him. He felt it a little embarrassing to be the master and degrade somebody as a follower -- a very nice, very delicate personality, the personality of a poet, of a singer, of a dancer.

Choosing Kyozan as his successor, and waiting for forty years -- what patience! -- almost transforming a stone into a diamond. But Isan was determined to make one point absolutely clear to humanity: if Kyozan, a simple and ordinary person, not belonging to any speciality, any category, without any talent, any genius -- if he can become enlightened, it will be a proof. To give this proof to humanity he chose Kyozan and worked hard on him. And the day Kyozan became enlightened, the day Isan transferred his enlightenment and the two flames became one, Isan disappeared from the world of matter, body, mind.

Kyozan was so radiant now. He was not only once enlightened, he was twice enlightened. His master has given him richer experiences, far deeper spaces, far clearer skies.

Source: http://www.oshorajneesh.com/download/osho-books/zen/Isan_No_Footprints_in_the_Blue_Sky.pdf