Rabbi Shimon explains the difference between dust and earth. Dust is barren and less important than the earth, from which arises all the goodness of the world. When Rabbi Yehuda questions him about the meaning of the verse, "He raises the poor out of the dust ..." Rabbi Shimon explains that dust signifies both humility and the moon, when she is not united with Zeir Anpin. He then applies this metaphor to the children of Yisrael, who are ruled by dust in Exile. This dust resembles night. When light appears and shines, however, the children of Yisrael shall obtain power and the Kingdom of Glory.
Without the Light of The Creator, man remains dark, barren, and as spiritually worthless as dust on the ground - because, like the moon, man has no Light of his own. Just as the moon derives its light from the sun, we receive our Light and spiritual sustenance from the realm of Zeir Anpin [the Upper Worlds]. When imbued with this Light, we receive divine fruits of goodness through our marriage partners, our children, and all of our endeavors in life.