During World War II, the U.S. submarine Tang surfaced under cover of darkness to fire on a large Japanese convoy off the coast of China. Since previous raids had left the American vessel with only eight torpedoes, the accuracy of each shot was essential. The first seven silent missiles were on target.

But when the eighth was launched, it suddenly deviated. Instead of hitting its intended target, it boomeranged back unseen to strike the crew that launched it. Too late, the emergency alarm to submerge rang out. Within a matter of seconds, the U.S. sub received a direct hit and sank almost instantly.

In the same way, we're also capable, while intent on attacking others, of doing irreparable damage to ourselves. The missiles of anger and hate we launch can return to hurt us.

Modern medicine now has documented proof that emotions such as bitterness and anger can cause headaches, backaches, allergic disorders, ulcers, high blood pressure, and heart attacks. Anger can be a poison that kills.