Arjuna said: "But, dragged on by what does a man commit sin, reluctantly indeed, O Varshneya, as it were, by force constrained?" The Blessed Lord said: "It is desire, it is wrath, begotten by the quality of mobility, all-consuming and all-polluting-know thou this as our foe here on earth. As a flame is enveloped by smoke, as a mirror by dust, as an embryo is wrapped by the amnion, so this is enveloped by it. Enveloped is divine wisdom by this constant enemy of the wise in the form of desire, which is insatiable as a flame. The senses, the mind and the reason are said to be its seat; by these, enveloping wisdom, it bewilders the dweller in the body. Therefore, O best of the Bharatas, mastering first the senses, do thou slay this thing of sin, destructive of wisdom and knowledge. It is said that the senses are great; greater than the senses is the mind; greater than the mind is reason; but that which is greater than reason, is He. Thus understanding Him as greater than reason, restraining the self by the Self, slay thou, O mighty-armed, the enemy in the form of desire, difficult to overcome." Ch. III-36-43.
Desires can never be satiated or cooled down by the enjoyment of objects. But as fire blazes forth the more when fed with butter and wood, so it grows the more when it feeds on objects of enjoyment.
If all the foods of the earth, all the precious metals, all animals, and all beautiful women were to pass into the possession of a man deluded by desire, they would fail to give him satisfaction.
Raja Yayati said: "O son, I have enjoyed with your youth to the full extent of my desires and to the full limit of my powers and according to their seasons-but desires never die. They are never satiated by indulgence. By indulgence they flame up like sacrificial fire with ghee poured into it. If one becomes the sole Lord of all the earth with its paddy, oats, gems, beasts and women, still it will not be considered by him enough. Therefore the thirst for enjoyment should be abandoned. The thirst for enjoyment which is difficult to be cast off by the wicked, which does not fail even with the failing of life, is truly a fatal disease in man. To get rid of this thirst is real happiness."
Understand that desire that is born of the quality of Rajas is man's enemy in this Samsara. The real enemy of the whole world is desire. It is from this desire that all the evils and miseries come to human beings. When desire manifests, it goads man to action and so he commits sins of various sorts. When a man's desire is not gratified, when one stands in the way of its fulfilment, he becomes angry. The desire gets transmuted into anger. When one is under the sway of anger, he will commit all sorts of sins. He loses his memory, intellect and understanding. An angry man commits murder. He himself does not know what he is exactly doing. He becomes very emotional and impulsive. All evil actions and evil qualities proceed from anger.
When desire gets hold of a man, it hides the knowledge of his true nature from him. Desire enshrouds wisdom, just as smoke enshrouds fire. He becomes egoistic. He gets deluded. He becomes a slave of passion and gets miseries of all sorts.
The Indriyas or senses bring the man in contact with external objects and the desires are thereby created. But the senses are not all-in-all. If the mind co-operates with the Indriyas, then only is mischief wrought. Mind is more powerful than the Indriyas. Mind is the commander. Reason is more powerful than the mind. Even if the mind brings a message into the mental factory by its association with the Indriyas, the pure reason can reject it altogether. Reason is more powerful than the mind. Behind reason is the Self who is the director and witness of reason and who is superior to reason. Desire is of a highly complex and incomprehensible nature. Therefore, it is very difficult to be eradicated or conquered. But with the help of pure reason all desires can be eventually destroyed. There is no doubt of this. Then you will get knowledge of the Atman which brings immortality, supreme peace and eternal bliss.