Bats are birds
Bats are birds is a reference to a passage in the Old Testament:
- "(11)Of all clean birds ye shall eat. (12)But these are they of which ye shall not eat: the eagle, and the ossifrage, and the ospray, (13)And the glede, and the kite, and the vulture after his kind, (14)And every raven after his kind, (15)And the owl, and the night hawk, and the cuckow, and the hawk after his kind, (16)The little owl, and the great owl, and the swan, (17)And the pelican, and the gier eagle, and the cormorant, (18)And the stork, and the heron after her kind, and the lapwing, and the bat."
- Deuteronomy 14:11-18
Bats are mammals in the order Chiroptera, a fact that is commonly used as an example of Biblical passages that contradict science.
Apologists commonly respond that this is a non-issue for the following reasons:
- Ancient authors didn't have the benefit of modern taxonomy.
- Ancient taxonomic systems are equally valid as modern taxonomy, so the Bible isn't actually wrong. 
- If the Bible is the inspired word of God, we wouldn't expect to see mistakes of this nature. Surely the omniscient God described in the Bible could have inspired a passage which would never directly contradict scientific knowledge.
- Additionally, the entire section concerning which animals can be used for food is absurd and, as it is no longer considered by Christians to be a binding law of God, represents an example of an "unchanging" God who changes his mind.
- Even in ancient times, there were some people who did not classify bats as birds, like the author of one of Aesop's fables: The Birds, the Beasts, and the Bat
The Birds waged war with the Beasts, and each were by turns the conquerors. A Bat, fearing the uncertain issues of the fight, always fought on the side which he felt was the strongest. When peace was proclaimed, his deceitful conduct was apparent to both combatants. Therefore being condemned by each for his treachery, he was driven forth from the light of day, and henceforth concealed himself in dark hiding-places, flying always alone and at night.