“It is he that sitteth upon the circle of the earth,”
It is often supposed that ancient people believed the Earth was flat. This conjecture – which we can show to be false – is used to criticize the truth of the Bible, or to suggest that the Bible teaches a flat Earth.
We can, however, challenge the assumption that ancient people believed in a flat earth. They did not. For example, in the third century BC, a man named Eratosthenes actually calculated the circumference of the Earth. It was already known that the Sun was directly overhead at noon at the Midsummer Solstice in the Egyptian city Syene. So Eratosthenes traveled north to Alexandra – a distance of 5,000 stadia, which had been repeatedly measured by frequent surveys. He measured the angle of the Sun’s rays in Alexandria to be 7°. This is about a fiftieth of a whole circle (360°), so he calculated the circumference of the Earth to be 250,000 stadia, which is 40,000 km or 25,000 miles. This is remarkably close to modern calculations. But the only reason he could do the calculation was because he knew the Earth to be spherical and lived in a society that believed the Earth to be spherical; otherwise, his famous calculation would not have occurred to him.
The Bible, as always, has the right of it.