In the simple meaning of the verse of "He separated between the water that is below the sky (/beginning of "outer space"/"firmamemt") to the water that is above it", Rashi says (and seems to imply) that the "sky" is the literal sky, and the "water above the sky" is physical water "hanging" above the sky, on the words of Hashem (seemingly different than the explanation in Shaar Hayichud vihaemunah chapter 5), in his words:.
"in the midst of the water: In the middle of the water (Targum), for there is a separation between the upper waters and the expanse, as there is between the expanse and the waters that are on the earth. Behold you have learned that they are suspended by the word of the King. — [Gen. Rabbah 4:3]"
And in verse 7
"above the expanse: It does not say, “on the expanse,” but “above the expanse,” because they [the waters] are suspended in the air (Mid. Ps. 19:4)"
So Rashi seems to say that the sky is the physical sky, and says the water is physical water. The explanation is difficult for me to understand.
What exactly does it mean?
Does it mean that there's the ocean, then the distance from the ocean to "outer space", (which is the "sky", or the "expanse"), then after the "sky" there's more empty space, then water surrounding all of that, and in that final expanse of empty space (equal to the distance from the ocean to the beginning of the "sky"), the words of "the king" are in it, keeping the water afloat, or does it mean that the words of G-d are in the heavens themselves?
But if so then where are the upper waters?
Directly above the physical "heavens", or still above the empty space above the heavens?
Seemingly, if Rashi means that the words of the "king" are in the "empty space above the expanse" (if that is indeed what it means), then the reason why the word of the king wouldn't be in the heavens themselves (as opposed to the empty space above it), would seem to be because of what Rashi said earlier, that the sky iself "thickened", in Rashi's words (earlier in verse 6):
"Let there be an expanse: Let the expanse be strengthened, for, although the heavens were created on the first day, they were still moist, and they solidified on the second [day] from the rebuke of the Holy One, blessed be He, when He said, “Let there be an expanse.” This is what Scripture says (Job 26:11): “The pillars of the heavens trembled” the entire first day, and on the second day: “They were astonished by His rebuke,” like a person who stands in astonishment because of the rebuke of the one who frightens him. [Genesis Rabbah 12:10]"
Which would imply the sky itself doesn't need the word, because it's thick, only the empty space above it would need the word.
I'm not sure if this is the explanation, but if so then a further question may arise, regarding what it means according to the Bal Shem Tov's explanation, on the verse in tehillin, in Shaar Hayichud vihaemunah chapter 1, that "forever your word stands in the heavens", implying the words are in the heavens themselves.
Although on the other hand, the fact that they solidified "because of the rebuke" of Hashem, could also imply that the "words of the king" are in it itself, which gives it thickness.
But if so then how would that fit with the next Rashi in verse 6, that seemingly implied that first there's the lower waters (ocean), then empty space above them, to the beginning of the "expanse", then the expanse itself, then other empty space, then the upper waters?
Further As mentioned earlier, that would imply that the word is in the second empty space, above the expanse (keeping afloat the "upper waters" that is even above that. Because if the word wouldn't be in the second empty space itself, then what would keep the waters floating above it?)
In addition, if the "thickness" of the heavens would be from the "word" of rebuke, then what would be the difference between the heavens themselves and the empty space above it (and Rashi implies they're two separate entities)?
So basically, what is the simple meaning of the "upper waters", where are they themselves, and where are the "words of the king" that they are hanging on?