I invite you to conduct an experiment. Sit facing the sea and watch a ship for several hours while it sails away into the sea. Little by little you’ll stop seeing it, not because it’s far away, but because it begins to sink into the horizon. If you read a history book, you’ll be surprised to find out that there was a time when most people believed the earth was as flat as a plate, and that when you reached the edge of the earth there was a great waterfall that fell into a precipice.
Many Greek philosophers (Pythagoras, Plato, Aristotle . .) had already noticed the earth was round. One of them, called Eratosthenes, had even calculated the perimeter (circumference) of the earth by measuring the different angles projected by the shadows of two tall towers. And surprisingly, he got very similar results to the ones that current technology obtains.
In the year 1519, Ferdinand Magellan and Juán Sebastián Elcano set sail on five ships off the coast of Seville, in Spain. They crossed the Atlantic Ocean, sailed through the Strait of Magellan, crossed the Pacific Ocean, and arrived in Cebu (Philippines). There Magellan was killed by natives. But Juán Sebastián Elcano proceeded with the expedition and in 1522 he reached the starting point, Seville, proving he had sailed around the earth and that it wasn’t flat, but round.
All those philosophers and explorers would have saved themselves the trouble if they had read the Bible, because many years ago it was written there that the earth is round. And who would know that better than its Creator?