Charles H. Spurgeon on Psalms 93:3

Their waves. The word k signifies a wave; because the water being dashed against a rock, or the shore, or another wave, is broken into spray. For the central idea of the word is breaking. And this aptly serves to picture the issue of those commotions and wars which are undertaken for the overthrow of empires and the church. For as mighty waves fill the beholders with horror, so great and powerful armies fill all things with fear and terror. But as the waves striking, in a moment are broken, and disappear, so the mighty power of kings and princes is often dissolved at one glance of God. The Church dwells in this life, as a rock in the waves, beaten by the waves of every tempest; but yet remains immutable, because the Son of God confirms and sustains her. Mollerus.