Joe Louis was the world heavyweight champion from 1937 until he retired in 1949. During his time of service in the army, Louis was driving with a fellow GI when he was involved in a minor collision with a large truck. The truck driver got out, yelling and swearing at Louis, who just sat in the driver's seat, smiling. "Why didn’t you get out and knock him flat?' asked his buddy after the truck driver had moved on. "Why should I?" replied Joe. "When somebody insulted Caruso, did ye sing an aria for him?" This is a great illustration because it's so relevant to the us understanding the source of our identity. The truck driver clearly didn't know the real identity of the person he was cursing, for if he had, he wouldhave treated him in a dramatically different way. On the other hand, Joe Louis knew who he was —the best boxer in the world—and therefore he had nothing to prove.
If you know who you really are, you have nothing to prove in life. You can sit back and simply enjoy life's ride!