Answer: We call any downfall “sin,” but do we really sin? In our world, it is considered a sin when I think that I can resist an act that I know is unacceptable, but still do it. But it isn’t really so because if I knew for a fact that it is prohibited, I wouldn’t do it.
Actually, sin is when I am overtaken and overpowered by the forces of separation. Sin is the state itself but not its cause. The cause always lies with the Creator. It is He who created our evil egoistic inclination.
How else can the evil inclination be created if not through “falling into sin?” First, it is necessary to ascend to the highest degree, fall from it, to receive impressions from all the degrees of ascent and our current state, and to cultivate the egoistic desire by means of the breaking of the soul. In fact, if it weren’t for the breaking, egoism would have remained at the animate level. Conversely, through the breaking, it grows to be a “creature,” “the evil inclination.”
Before the breaking, it was just a will to receive pleasure, an animal. If a lion, for instance, wants to kill a deer, we don’t consider it to be an evil inclination; a lion is simply moved by instinct, a desire to be filled.
So, when does the evil inclination appear? It appears when we ascend, receive forces of love and unity there, then fall with them and the forces turn into their opposite: unfounded hatred. Now the desire to feel pleasure, which includes all the informational data (Reshimot) that are pushing it toward this unfounded hatred, is called the evil inclination. From this moment on, it wishes to use everyone else to their detriment because that is what it enjoys.
In other words, in a human appears a sensation of another human (which animals don’t possess), and he enjoys when the other suffers. That is genuine egoism! In contrast, good is when I turn this hatred into love. Yet, a relationship with the other is necessary in both cases.
From the 3rd part of the Daily Kabbalah Lesson 7/15/10, Talmud Eser Sefirot