If the Upper Partzuf wants to give something to the lower, it reduces itself like a mother that cares for a child. She makes “adult” food for herself, but for the baby she makes special food, heated to a specific temperature.
These additional actions, which are done through a special mechanism of the Upper One’s connection with the lower one, are called “Searot” (hair). It comes from the word Soer (stormy) or Saara (a storm).
The Upper One wanted to give the lower one everything He has! But He had to restrict Himself and give the lower one just a little bit according to the lower one’s level, as much as he is able to receive. The Upper One has to ensure that the fulfillment will benefit the lower one.
This restriction or the force with which the Upper One restrains Himself is called “Searot” (hair), which has a similar sound to how everything rages (Soer) inside of Him due to this.
But He looks at us and sees that there is nothing to give to anyone. No one wants to receive anything. How great is the suffering of looking at babies who are nearly dying of hunger, while being able to help them, having the ability to cure all of our pains and fill them with goodness, while we do not want it! We are unable to accept anything from Him.
The echoes of this storm, which the Upper One uses to restrain Himself, the impure forces, Klipot, begin to influence us, trying to awaken us and force us to act. It seems to us that we are influenced by evil forces, but they awaken only to the degree we fail to advance, falling behind in our development and not letting the Light fulfill us.
From the 2nd part of the Daily Kabbalah Lesson 12/6/10, Talmud Eser Sefirot