Baal HaSulam writes that everyone has to study the wisdom of Kabbalah, because this is the reason a person is born: to correct himself.
Our world emerged due to the breaking of souls, when the single, unified soul partitioned into billions of pieces – individual souls. Today we are in the state of separation, which we perceive in the form of “this world.” In reality, however, there are no lower or upper worlds; they are just products of the human perception of the degree of connection between the souls.
“The world” is a degree of connection among the souls. The current degree is “this world.” If the souls begin coming closer to one another, then the increased interconnection among them will be called, “the World of Yetzira.” An even greater connection is, “the World of Beria,” and so on.
As we strengthen the connection between the souls, we will consecutively feel all the worlds. We will ascend up the levels of the worlds all the way until the World of Infinity, where everything is one.
Kabbalah is the method that helps all the souls to unite into the corrected state. This is why it is so vital to us.
(From Part 3 of the Daily Kabbalah Lesson)