A resident of Mezhibuzh had a quarrel with another. Once, while in the Baal Shem Tov's shul, he shouted that he would tear the other fellow to pieces like a fish.

The Baal Shem Tov told his pupils to hold one another's hands, and to stand near him with their eyes closed. Then he placed his holy hands on the shoulders of the two disciples next to him. Suddenly the disciples began shouting in great terror: They had seen that fellow actually dismembering his disputant.

This incident shows clearly that every [thought and spoken word] has an effect - either in physical form or on a spiritual plane - that can be perceived only with higher and more refined senses.

HaYom Yom, entry for 29 Tishrei