Some argue that the Bible cannot be inerrant because Leviticus 11:13-19 says that the bat is a bird, when in actually it is a mammal. However, there is a very simple explanation that solves this alleged mistake in the Bible.
13 “And these you shall detest among the birds; they shall not be eaten; they are detestable: the eagle, the bearded vulture, the black vulture, 14 the kite, the falcon of any kind, 15 every raven of any kind, 16 the ostrich, the nighthawk, the sea gull, the hawk of any kind, 17 the little owl, the cormorant, the short-eared owl, 18 the barn owl, the tawny owl, the carrion vulture, 19 the stork, the heron of any kind, the hoopoe, and the bat.Leviticus 11:13-19
The Bible is not meant to be a scientific or technical textbook, and the classification of bats as mammals is a relatively modern classification that did not exist in ancient times.
The most reasonable interpretation of Leviticus 11:13-19 is that “bird” is simply defined as animals that flew, which includes bats.
The assertion that there is a contradiction here is based upon a faulty assumption about what the Bible is actually saying in Leviticus 11:13-19.
There are some foundational principles that apply to all alleged and apparent contradictions in the Bible. To read more, see Bible Difficulties: Foundational Principles.
To read more answers to alleged and apparent contradictions in the Bible, see “Contradictions” in the Bible Answered.
These books are also excellent resources: