What is the meaning of "v'El Mi Sedameyuni v'Eshveh"?
Radak: To whom can you compare Me, that I will resemble the matter?! You cannot compare Me via your words without intellect. I do not resemble [anything] due to your comparison. I am alone, and created the entire world.
Radak: I disputed with you, that images have no semblance to Hashem. Also what I depicted that He sits in Shamayim or in the middle [of the world], was only according to your limited intellect, which cannot fathom power without physicality that exists in a particular place. Dimyon can apply to things that are unequal - "Domeh Dodi li'Tzvi" (Shir ha'Shirim 2:9). However, you cannot compare Me to something that equals Me in quantity or quality.
Why does it say "Yomar Kadosh"?
Radak: He is Kadosh, and the Master of thoughts.