In Buddhism, knowledge is regarded as an obstacle to understanding, like a block of ice that obstructs water from flowing. It is said that if we take one thing to be the truth and cling to it, even if truth itself comes in person and knocks at our door, we won't open it. For things to reveal themselves to us, we need to be ready to abandon our views about them.
The Buddha told a story about this. A young widower, who loved his five-year-old son very much, was away on business, and bandits came, burned down his whole village, and took his son away. When the man returned, he saw the ruins, and panicked. He took the charred corpse of an infant to be his own child, and he began to pull his hair and beat his chest, crying uncontrollably... He organized a cremation ceremony, collected the ashes and put them in a very beautiful velvet bag. Working, sleeping eating, he always carried the bag of ashes with him.
One day his real son escaped from the robbers and found his way home. He arrived at his father's new cottage at midnight, and knocked at the door. You can imagine at that time, the young father was still carrying the bag of ashes, and crying. He asked, "Who is there?" And the child answered, "It's me Papa. Open the door, it's your son." In his agitated state of mind the father thought that some mischievous boy was making fun of him, and he shouted at the child to go away, and he continued to cry. The boy knocked again and again, but the father refused to let him in. Some time passed, and finally the child left. From that time on, father and son never saw one another: After telling this story, the Buddha said, "Sometime, somewhere you take something to be the truth. If you cling to it so much, when the truth comes in person and knocks at your door, you will not open it."
Guarding knowledge is not a good way to understand. Understanding means to throwaway your knowledge. You have to be able to transcend your knowledge the way people climb a ladder. If you are on the fifth step of a ladder and think that you are very high, there is no hope for you to climb to the sixth. The technique is to release. The Buddhist way of understanding is always letting go of our views and knowledge in order to transcend. This is the most important teaching. That is why I use the image of water to talk about understanding. Knowledge is solid; it blocks the way of understanding. Water can flow, can penetrate.
~ Thich Nhat Hanh from “Being Peace” ~