A poem is not a textbook. The Bible, as you say, is also not a textbook, and it should not be read as one.
The commonality, though, is that the rules of the language determin the initial understanding of the message in the scribblings put down on the page.
I'm not contesting this, xzins. :^) You need to know the rules of language — its syntax — in order to understand its message — its semantics. But semantics does not "reduce" to syntax.