Some people treat it like one, but even a cursory look
reveals it’s considerably more complex than that. It is a collection of
history, poetry, ancient law, prophecy, doctrine, personal letters and more.
Despite the fact that it is a compilation, the Bible is somewhat systematic in
the sense that there are lessons taught consecutively from Genesis to
Revelation that build on what has already been established. That should not surprise
us if we believe it to be divinely authored. The final few books (from Romans
on) are perhaps the most pointed and direct in addressing how the reader ought
to respond to it.
But its format is not “textbook-y” in the least.