Chögyam Trungpa Rinpoche

Excerpt from Light Rays of the Sun and Moon

an autobiographical doha by Trungpa Rinpoche, on the occasion of learning of the death of one of his teachers, Rolpe Dorje.

In particular, my teacher had nurtured me
   with maitri in accord with the dharma.
When I thought again and again of how great
   his kindness had been,
At first there arose a great feeling of sadness,
But then even the finest hairs of suffering
   dissolved into the natural state.
I rested in the wisdom mind of the guru,
Who bestowed a rain of blessings right there.

The Lion's Roar

In the tantric tradition, the sense of the guru plays an extremely important part. The reason why the guru plays an important part is that you are desperate. And when you commit yourself into a more involved situation like tantric discipline, the guru's word is regarded as absolute supertruth, not just ordinary old truth, but vajra truth, truth with power behind it. If you reject such a truth, you can get hurt, you can be destroyed. So you commit yourself to the guru in a threefold way. The form of the guru is regarded as a self-existing manifestation of the truth in the search for the basic sanity of vajrayana. The speech of the guru is regarded as a mantra, a proclamation; anything from him on the sound or intellectual level is absolutely accurate. If you doubt that, you can get hurt, destroyed, your intuition can get cut down. And the mind of the guru is cosmic mind. If you doubt his mind, again you can get hurt, because you could end up suffering from insanity, a fundamental freak-out of ego. (p. 180)