BG 3.37-39
The Blessed Lord said: It is desire, it is wrath, begotten by the quality of motion; all-consuming, 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 wisdom by this constant enemy of the wise in the form of desire, which is insatiable as a flame.