When we advance in our work, we first have to accept that there is no evil without goodness and that there is no goodness without evil. We have to reach the final state in which all of the evil is revealed and in against it all the goodness; one sustains the other as “the advantage of the Light in the darkness.” The greater the darkness, the better chance we have to discover a greater Light in contrast to it.
This is how the creation is arranged because we always find in it two forces, two parts, two attributes, which are basically the Creator and the created being.
So if we want to advance, we have to know in advance that we can do so only by increasing the negative force and the positive force in contrast to it. But the negative force grows first; as it says: “And there was evening and there was morning, one day.” So they keep appearing alternately, the negative force and the positive force, negative and positive.
Our role is to find the place for the middle line in which we can exist and determine our balanced states. This balance is possible only if we unite and connect. Then each one adds his own state to everyone else, and thus we bring everyone to a state of balance.
If we examine the balance point, we will discover HaVaYaH in it that is direct and opposite, the ten Sefirot of the Direct Light and the ten Sefirot of the Returning Light, which is a whole spiritual structure called a Partzuf. This is the structure that reaches a state of balance.
It is an elementary principle, two opposite forces that reach a state of balance and thus establish all of reality.
From the Preparation to the Daily Kabbalah Lesson 12/27/13