A sharp contrast exists between a state of global collapse and the presence of a stabilizing force that provides a firm foundation for existence. The world may appear to melt and tremble in fear, yet a solid base remains to keep creation intact.
The primary approach among commentators is that God is speaking, looking toward the future. When the time comes for God to pass judgment upon the enemies of Israel, sheer terror will grip the inhabitants of the earth, and their hearts will melt with fear [רד״ק, מאירי]. This profound shaking of the world serves a specific purpose. It is designed to bring humanity to a deep realization. Out of the terrifying collapse, everyone will come to understand that God created the world out of nothing and firmly set its mountainous foundations in the past. Humanity will recognize that just as God establishes the pillars of creation by His will, He possesses the absolute power to shake them, alter the laws of nature, and rule the world exactly as He desires [רד״ק, אבן עזרא, שטיינזלץ, אלשיך]. Ultimately, this recognition leads to a genuine faith in God's divine providence, the reality of reward and punishment, and His supreme authority [מאירי].
Alternatively, another perspective identifies the nation of Israel as the speaker, placing the events at the revelation at Mount Sinai. According to this view, when the nations of the world refused to accept the Torah, the earth faced a very real existential threat. It came dangerously close to reverting to a state of absolute emptiness and chaos, a condition that was stipulated at the very dawn of creation. However, when the Israelites accepted the Torah and committed themselves to obey, they essentially saved the world from total destruction. Through this profound acceptance, the Israelites became the ones who stabilized the foundations of the earth, setting them firmly in place for all eternity [רש״י, מצודת דוד].
Adding another layer to this concept, the destiny of the Israelites following their long exile is brought into focus. When they finally attain peace and tranquility, they will not spend their free time and holidays engaging in idle pleasures like the surrounding nations. Instead, they will dedicate those moments entirely to serving God. Because of this unwavering spiritual devotion, even when the world around them quakes and falls apart, the Israelites act as the ultimate stabilizing force. They bring divine truth to light, offering lasting meaning and steadfast stability to the entirety of creation [מאירי].