All that we feel and see around us is only a play between the Light and the vessel (Kli), the Light and desire. And since they differ in their properties, in the middle between them, there is the world, the reality that we perceive. It represents exactly what we still lack in order to attain the world of Infinity.
That’s why the word “world” (Olam) means “concealment” (Alama). All forms of life that we observe around us, namely, the still, vegetative, animate, and speaking levels either in the material or spiritual world, show us the deficiency that we need to “fill” in order to reach Infinity.
After all of them disappear, we see only the Light that completely fills all desires, the entire sphere; it indicates that we have reached the corrected state. Until then, we feel all kinds of forms, and this is a sign that we have not corrected all the desires to become similar to the Light, the property of bestowal.
From Kabbalah for Beginners, “Perception of Reality” 10/20/10