Contextually ung word na ginamit jan mas malapit sa Filipino words paligid, palibot o napapaloob rather than bilog.tingin ko boss yung circle diyan means "around" like when we say "all around the world" which means in every place on earth
5th B.C. na nagsimula ang round earth, yung bible is around 15th B.C. so flat earthers pa tayo sa panahong iyan
Probably they are flat earthers, but i dont think they really care about the shape of the world. Yung specific part nga na book na yan is like a chant na nirerecite nila during the travel after the exile i think from Babylon. It is more about politics and how they predict god will help them, and so on. Wala kasi mass media noon, so that is how the make propaganda.