A student of Zen Buddhism circled around the world looking for a teacher. Finally, he discovered a famous zen master and went to see him. The student was so excited about meeting with the master that he tried to tell him everything he knew. As the student went on, the Zen master asked: do you want some tea? The student replied: yes. The master started pouring the tea. The student kept on talking. He saw that the cup was full, but the Zen master was continuing to pour, spilling tea all over the table. The student was confused. He asked: Master, the cup is full. Why do you keep on pouring? The master replied: the cup is a lot like you. You are so full of wisdom already that there is no room for anything else to go in.
Source: The Power of Kabbalah – by Yehuda Berg