To explain: Our Sages declare,1 “The Evil Inclination is like a fly sitting between the two openings of the heart.” Its only concern is its own desires and yearnings. Like a mosquito which takes nurture into its body, but does not give forth, so too, the animal soul thinks only of itself. As it is said,2 “The eye sees and the heart craves.” Likewise, the Jerusalem Talmud (Berachos 1:5) states: “The eyes and the heart are two brokers for sin.” [The process] begins with sight. As our Sages comment (Sotah 8a), “The Evil Inclination does not rule over anything unless it can see it.” After a person sees something, his heart begins to hanker after it, and he follows its whims.
The basic reason for this is a person’s exceeding self-love, his high regard for himself. This is why he indulges himself, allowing his heart free rein without any restraint or limit. Not only does he not fear G‑d at all,3 but he acts like a wild animal, attacking and stealing in many different ways to fulfill his heart’s desires.
As we see for ourselves, there are people who follow the desires of their hearts, heaven forbid; all their thoughts, words and deeds are oriented to what they crave. This attitude results from the seductive craft of the Evil Inclination which incites a person, and leads him from one downfall to the next, heaven forbid.
