But then the latter part of Krishna's life has two very important aspects. One aspect teaches us that life is a continual battle, and the earth is the battlefield where every soul has to struggle, and the one who will own the kingdom of the earth must know very well the law of warfare. The secret of the offensive, the mystery of defense, how to hold our position, how to retreat, how to advance, how to change position, how to protect and control all that has been won, how to let go what must be given up, the manner of sending an ultimatum, the way of making an armistice, the method by which peace is made -- all this is to be learned. In this life's battle man's position is most difficult, for he has to fight on two fronts at the same time: one is himself, and the other is before him. If he is successful on one front, and on the other front he proves to have failed, then his success is not complete.