Young-earth creationism claims to take Genesis literally. It insists that the firmament mentioned there is not a solid dome, and that the “water above” the firmament were water vapors, a vapor canopy that provided the waters for the global flood.
Unfortunately for this view, there is no evidence for it from the natural world. But young-earth creationists are notorious for ignoring scientific data, if they think that the Bible justifies their doing so.
But unfortunately for them, the Bible is also against them.
In Psalm 148:4, the author, writing in a time when it made sense to mention the people of Israel (v.14), referred to waters above the firmament.
Some translations try to obscure the meaning. But to no avail. Clearly this cannot be a post-flood water vapor canopy, since young-earth creationists claim that the post-flood world was radically different from the pre-flood world.
The most natural way to take it, of course, is as an indication of the view of the natural world that the psalmist had, which he or she shared with other ancient peoples, in which the sky was solid and there was water above it.
That’s what young-earth creationists would believe, if they took the Bible literally.
But they don’t, and they won’t.
Images in this post come from a blog post about the “expanse” on the blog “Letters to Creationists.”