Tetzaveh: Chapter 11
"Blow a Shofar at the new moon"

The old sage continues by saying that at the new moon, on the feast day, Harsh Judgment awakens and strengthens the Other Side; then the whole world is under Judgment, as the moon, Malchut, radiates no light. All the acts of correction that preserve the worlds arise from the lower beings if their deeds are correct; if they are not, Malchut remains without illumination until the wicked are separated from the righteous, and then Judgment awakens. We learn that God gave the Shofar to Yisrael in order to break the covering on the moon that prevents it from shining; the sound of the Shofar arouses Mercy below and Binah above. The upper world, Binah, always gives to the lower world, Malchut, according to its present state, so human gladness below draws supernal gladness. The old sage says that on Yom Kippur Malchut lights up with a supernal illumination from the light of the World to Come, Binah.