The migrated question asks specifically about “the sky”, a word lacking a direct equivalent in the Hebrew, the closest being heaven, and secondly asks “if the Bible...”, which excludes by extension the opinions of modern secular experts or doctrines of accommodations including John Calvin’s (Luigi Piccardi, W. Bruce Masse, Myth and geology, p. 40) much later reinterpretation of firmament to mean clouds. The text cannot be gently nor violently forced to say what it did not say the first time to the intended audience, no matter how much cognitive dissonance it produces to a modern reader or conflicts with accepted norms of secular modern cosmology.
Firmament
The quoted text speaks of the firmament dividing the waters from the waters. This puts emphasis on the firmament לרקיע and on the waters. This divider is explained and described in numerous other passages of Scripture. It’s derived from the word רקע which means to beat out into a thin sheet. This is exactly the same idea seen numerous places in Scripture that the heavens are spread out.
“who stretches out the heavens like a curtain, and spreads them like a tent to dwell in;”
Isaiah 40:22
The heaven and firmament being one and the same based on the quoted text
“And God called the firmament Heaven”
Genesis 1:8
Liquid Waters
With regards to the waters. Waters being divided by necessity must be the same water below and as the waters above the firmament divider. It cannot be physical liquid water below and immaterial “spiritual” water above. It likewise cannot be alluding to a myriad of people, symbolism, for then there must likewise be people below and above the firmament divider. Not neglecting the fact that Adam the first man was not yet even created.
The authority of Scripture over claims of scientific facts
What is remarkable is the willingness to divert from what is written in the Biblical text to what is presumed to be true in modern cosmology in an effort to mash the two incompatible paradigms and corresponding axioms together. This is most unfortunate and improper. Whatever one chooses to believe about secular modern cosmology becomes irrelevant to the ancient text because the text was not addressed to a modern audience. Therefore the cosmology of the ancient audience must be understood and read into the ancient text. Hermeneutics demands it be so.
Biblical text is not assisted by extraBiblical opinions. It doesn’t require assistance and it cannot be overruled by extraBiblical opinions. Meaning no extraBiblical explanations should, will or can stand as an authority over the written text, especially a much later idea created by men and entirely uninspired. Even at the expense of nullifying the entire Scripture as erroneous, uninspired and fallacious the text must not be tampered with.
The text states what it states and either it is true or false, accept or rejected, believed or discarded but it cannot be improved, tweaked or helped by modern opinion. The text must mean what it was intended to mean to the audience of that day when the text was written and to whom it was addressed. This is plainly, basic hermeneutical prerequisites. If the text is modified, then it has been corrupted.
While extraBiblical passages from the same time period can shine light on the meaning of the firmament רקיע in Hebrew, στερεωμα in the Greek, there are sufficient texts within the OT to show and describe what it is. A hard beaten out structure dividing and holding up immense volumes of water above.
The waters above the firmament in the heavens are liquid in form. The Hebrew and the Greek have words for clouds, mists, vapor, rain and yet the word for water is explicitly and intentionally used. As for example by the psalmist after the world wide flood during Noah’s day. This nullifies the bizarre theory of layer of water prior to the flood but not also afterwards. In fact the same psalm later speaks of mist, showing that there is a difference between what the psalmist meant when he said water above the heavens and not mist, clouds or steam.
“Praise him, you highest heavens, and you waters above the heavens!
Praise the Lord from the earth, you great sea creatures and all deeps, fire and hail, snow and mist, stormy wind fulfilling his word!”
Psalm 148:4, 7-8
Concluding remarks
In answering the question asked in the title, no the Bible does not say the sky has water in it, it says the heavens above the firmament has water in them. The sky as understood today contains water in the form of gaseous water droplets, and condensed together they would equate to a sea of water but the text quoted specifically speaks of liquid water. The hard structure expanse has liquid water below and above it, not just below it.