Fair question.

Educators in doctrinal religions generally have to stick to the doctrine. Doctrines are sometimes inconsistent. And secondary school educators aren't distinguished scholars so they sometimes make a doctrine appear more inconsistent than it is because they aren't great at nuanced or obscure aspects.

Linguistic and cultural shifts sometimes play a role. I've heard it explained that, "It is easier for a camel to go through the eye of a needle, than for a rich man to enter into the kingdom of God" is a reference to ancient walled cities that would shut the main gates at night to protect against attacks on the town. A merchant who arrived late would have to use a much smaller secondary gate and would have to unload merchandise at the edge of town to fit his camel through. So it's an idiom similar to how we say bottleneck, not a miraculous claim about a camel fitting through a sewing needle.

Disclaimer: I do not have the scholarly chops to assess that particular explanation.

So to bring in a non-religious example, the earliest written reference to cotton in European history is a passage from the ancient Greek writer Herodotus. He's describing imported textiles from India. He uses the word wool--then he adds context to explain that he really means cotton. Many generations later in the Middle Ages, a popular book called The Travels of Sir John Mandeville claims that in a place called Tartary (roughly Central Asia) a plant grew that sprouted actual lambs which people would harvest and shear for their wool. It's dubious how seriously people took that book even in the fourteenth century but some modern scholars who think the people of the Middle Ages were credulous simpletons have traced the origin of the "vegetable lamb" myth all the way back to Herodotus because of his use of the Greek word for wool. There's a catch, though: ancient Greek didn't have a word for cotton. They couldn't grow cotton in Greece back when Herodotus was alive and cotton fabric was rare enough that they put other words into service when they needed to describe it. For a long time English didn't have a word for cotton either; the OED says it entered the language in the early fourteenth century as a borrowing from Arabic--right around the time when The Travels of Sir John Mandeville was published. So Herodotus probably didn't think sheep grew on cotton plants. And the only reason anyone imagines he believed that is because centuries later someone decided to make up a ridiculous story.

Another non-religious example are the kennings in Beowulf. Kennings were compound words that fit poetic meter. The author would sometimes write "whale road" where he meant the sea and would sometimes write "light of battle" to mean sword. This may have inspired J.R.R. Tolkien to describe magical swords as glowing because Tolkien was an academic Medieval scholar but it does not mean that the Anglo-Saxons thought Beowulf owned a magical glowing sword.