Trorbes
Placidius
Bats are birds as long as you classify them as such. Just because an ancient text doesn't agree with todays taxonomy does not make it wrong by the standards of its time.
Modern taxonomy isn't just random assignment of species, you realize. Bats are quite obviously mammals. Mammals and avians are quite obviously different. One would think God would be realize this, wouldn't one?
"Bird" doesn't necessarily equate to "avian" in ancient literature, much like "bug" doesn't necessarily equate to "hemipteran" today. Dragons were called "serpents" (wurms), monkeys were called apes and vice versa (they still are today, but you can now beat someone with a dictionary if they do that.) Vulgar names tend to have loose definitions, and the association between a specific clade and a vulgar name is obviously quite modern. It's silly to call a beetle a coleopteran and a butterfly a lepidopteran when the target audience just calls them bugs, unless you're writing a science textbook or something.
Now if the Bible had said "chiropterans are avians"... of course it'd never have said that because the terms didn't exist, but then again the word "bird" as defined today didn't exist either.
(I heard the hebrew word used essentially translates to "flying thing", by the way.)