Once upon a time the world really was flat. God had decided to take an iron and flatten it. It happened before he placed living things on the planet, but the Bible didn’t include that part.
People back in the time the world was flat were correct in their deducing. There was an edge that fell down into oblivion, but then God filled the earth with helium, and it took a quite few years for them to realize that.
So when remembering history, don’t forget the time when God was bored, heated up a very large iron, and made the world as flat as a pancake. And understand that deities, not just humans, must also find ways to amuse themselves.