On religious literature.
I agree that it’s sacredness is because of it’s immutability. I don’t agree that that forces it to be read a certain way. Just the opposite. Because it is enduring, it can be read many ways. I don’t know what this implies for a treatise, that was out of circulation for centuries or that was secret manual that is now publicly available. The Zohar can serve as a loose example of either scenario.
But anyways, just a mere insistence that it can be – or even should be read as literature, is not a denial of it’s metaphysical truths. It is just an obvious reference that Herder was likely not initiated in those same truths.