Which Resha'im are discussed?
Rashi: Those who do not put to heart to repent.
Radak: This discusses the end of Resha'im - "v'Hayu Chol Zedim v'Chol Ose Rish'ah Kash [v'Lihat Osam ha'Yom ha'Ba]" (Mal'achi 3:19). This verse is connected the next verse - "Ein Shalom
What is the comparison to "Yam Nigrash"?
Rashi: The sea, the entire day it is Goresh (expels) mud. Its waves are haughty to rise and leave the border of sand that I put for them (Yirmeyah 5:22). When it gets there, it is broken against its will. Its fellow wave sees this, and does not retract. So the Rasha sees his colleague stricken for his evil, and he does not retract. And just like the sea, its mud and stench are on its mouth, so Resha'im, their stench is in their mouths. E.g. Pharaoh said "Mi Hashem" (Shemos 5:2), Sancheriv said "Mi b'Chol Elohei ha'Aratzos
Why does it say "Hashket Lo Yuchal"?
Radak: The sea cannot be calm. Wave after wave comes; it never rests. When it comes to the bank, its water expels mud. [So 1 ] Resha'im never rest from making tumult in the world, until they will die - "Sham Resha'im Chadlu Rogez" (Iyov 3:17).
Malbim: The Ru'ach arouses on the heart evil images for every sin rooted in Resha'im's Nefesh. This Ru'ach storms in them, until its waters expel mud. It clouds their intellect and Midos with desires and bad natures, to the point that they cannot have Shalom of the Nefesh to quiet its anger.
It seems that the text of Radak should say 'Ken', but I did not find so in any text. (PF)