When once a person's inclinations, fancies, and tendencies have grown stronger than his will-power, he experiences in his life several enemies existing in his own self, and he finds it difficult to combat them. For inclinations, fancies, and tendencies, when powerful, do not let will-power work against them. If there is any such thing as self-denial, it is this practice; and by this practice in time one attains to a power which may be called mastery over oneself.
Life is a continual battle. Man struggles with things that are outside him, and so he gives a chance to the foes who exist in his own being. Therefore the first thing necessary in life is to make peace for the time being with the outside world, in order to prepare for the war which is to be fought within oneself. Once peace is made within, one will gain by that sufficient strength and power to be used through the struggle of life within and without.