"will see that things go well for the godly person." The word "this" refers to everything good that the writer has described in the previous verses about the godly person.
The grinding of teeth is an expression of extreme anger. See how you translated a similar phrase in [Psalms 35:16](../035/016.md). (See: [[rc://en/ta/man/jit/translate-symaction]])
The writer speaks of the wicked person's eventual death as if that person were something, such as ice, that can melt. Alternate translation: "eventually die" (See: [[rc://en/ta/man/jit/figs-metaphor]])
Possible meanings of "desire" are 1) the emotional desire that wicked people have. Alternate translation: "the things that wicked people want to do will never happen" or 2) it is a metonym for the things that wicked people have desired. Alternate translation: "wicked people will lose the things that they desired" (See: [[rc://en/ta/man/jit/figs-metonymy]])