A River That Cannot Be Frozen
Generally speaking, Buddha and sentient beings are like one river. Buddha, however, realizes the nature of the self and, free of doubt, sees that all the activities of samsara are like a dream or illusion. Buddha's mind abides like the nature of peace -- like a river that cannot be frozen. Sentient beings, on the other hand, have not realized their own nature, and their minds are influenced by conditions which cause afflictive emotions. This is like meeting very cold water and freezing, the ice then becoming like a rock that cannot be broken.
If the heat of devotion and compassion melts the frozen mind, one will realize there is no difference between oneself and Buddha. Therefore, the single most important source of blessing is devotion. It's like a hundred rivers going under one bridge.
When you look at your mind just after strong devotion, that awareness is the cause of attaining enlightenment. Within that, look again at the very face of the awareness. It dissolves into emptiness -- both subject and object. A beginner does not believe it, but this dissolution is Buddhahood. Therefore Tilopa said, "Seeing nothing is the supreme insight."
It will not last long, so meditate for a short time, again and again each session. This will dispel obstacles and enhance your meditation.
Devotion is the single essential point. When you practice devotion, visualize the lama in front of you in space as actually residing there. The lama's mind is Buddha, so when you supplicate, the blessing will be definite, and the lama will keep you in his or her mind.
--His Eminence Garchen Rinpoche