For some reason Himmel is plural here.
Because it's plural in the Hebrew. Or more accurately, a dual. Hebrew has three numbers for nouns: singular, dual, and plural. So does ancient Greek.
Mayim means "[two] waters," and the word Luther renders as
die Himmel,
shamayim, derives from it -- the "[two] sky waters." English translators also translate
shamayim as "heavens" instead of "heaven." Even today, we in English use a poetic plural, e.g. "The heavens opened" to indicate rain, probably irrespective of the question of translation from Hebrew. Number in Hebrew doesn't always connote cardinality. Here it's more likely to be a "majestic" dual. Making something dual or plural -- even when it's clearly singular (or where number is meaningless) -- endows the word with greater importance and power. The jury of Semitic linguistics is still pondering whether that's the case for
mayim. In any case t's up to the translator to decide what to say in a language that has different conventions. For example, the Hebrew word for Egypt,
Mitzrayim, is also a dual. It literally refers to the
two Egypts because back then the notion of Egypt was as a late unification of the Upper and Lower Kingdoms. Now the translator could easily adopt a construct such as what we mean when we say "The Americas," but that would be confusing. So he just uses the concept familiar to English speakers -- one Egypt.
You point out the etymological fallacy, which is quite pertinent to the discussion, but it wasn't exactly where I was going with that. Putting together two words, say
sha +
mayim, to create a new word is an example of a derivation. The Gesenius lexicon for Hebrew is immaculately researched on points like this. The derived word isn't always meant forever to be a concrete combination of its constituents. "Mortgage" doesn't literally mean "death pledge," although that's what you'd think if you tried to define it solely by the constituents from which it was derived. In Hebrew as in English, the derived word takes on a meaning of its own, and may take on meanings for symbolic or poetic purposes that have nothing to do with its derivation. I could write, "We've mortgaged our future by a short-sighted energy policy," and that would use "mortgage" to mean a diminishment of use or potential.
Translation is different. The path that arrives at the Hebrew word
shamayim can be wholly different than the path that arrives at the English "heaven." Each of these words has its own derivation according to its prototypical languages or related languages. Each brings with it a certain linguistic baggage. At some point, however, a translator decides that there is enough congruence between the two present meanings of those words that one can stand for another. To say "heavens" derives from
shamayim (or, for that matter, that "firmament" derives from
raqqiya) is misleading. No, it's outright incorrect. We've decided that the English word "firmament" is the best word to represent the Hebrew word
raqqiya. That has nothing do with how either "firmament" or
raqqiya was derived. Amusingly, Jr Knowing insists that
shamayim and
raqqiya must be distinct and that "firmament" and "heavens" must also be distinct. He's all at sea when it comes to understanding how Hebrew poets write. The structure of Ps 19:1 (actually it's v. 2 in the Hebrew numbering) mandates that
shamayim and
raqqiya must -- here, at least -- evoke a common image. And to throw a wrench in the works, "heavens" is a term in Elizabethan theater meaning the removable ceiling over the thrust stage. As you might expect, Jr Knowing is simply making up stuff to suit his purposes.
Along those lines, in his rush to tell us the limitations of the "firmament," he has told us that
raqqiya means a solid dome. That's true enough. It doesn't have to be dome-shaped; it can be flat surface such as a desert floor. It's derived from a root meaning to beat out or flatten as with a mallet. Less often it can mean a figurative "extent," or also the title of the James S.A. Corey novel series. That would be an example of a meaning that transcends its literal derivation. In very ancient Hebrew cosmology, though, it means dome-shaped, and it conveys solidity. We refer to the other extra-Biblical meanings to help inform us what nuances might apply to a Bible reading. But Jr Knowing took solidity also to mean it was impenetrable, impermeable. That is not a connotation of
raqqiya. That's certainly what he needs it to mean in his von Braun fantasy, but in very old Hebrew cosmology the firmament is certainly permeable because that's how you get rain. And the Lutheran commentator to which I referred him said as much. That's probably why Jr Knowing has been evasive about that. There is absolutely nothing in Hebrew cosmology or Lutheran exegesis that says the
raqqiya is impenetrable.
The final laugh comes, as Von_Smith has just noted, when you see the contradiction in his recent approach. Jr Knowing has fallen all over himself telling us that von Braun, as a good Lutheran, would have read the Bible literally, and that this means he would have considered the "firmament" to be impenetrable. But when I ask Jr Knowing to render the verse literally from the Hebrew to support his paraphrase, "the firmament did its job," he can't do it. He has to lapse into a figurative (and wholly ungrammatical) rearrangement of the concepts in the verse to arrive at his desired meaning. The only way he can get the verse to mean what his argument requires it to mean is to paraphrase it and radically change its meaning, not read it literally. That's probably why he evaded my requests for so long that he do so. Once he did, his hand was tipped.
Rest assured Jr Knowing's linguistic and theological skill is just as inadequate as his engineering skill.