Comment on New forum by Richard.
The Bible (Authorized King James) is the only absolutely reliable source of truth at all in this very unreliable world. It is confirmed by logic and observation. With this as my basis I will answer:
If this concave Earth theory were true, then the Bible would say that Heaven is inside the Earth, rather than it saying that Heaven is above the Earth. Hell is “beneath” or that is, inside the Earth, and Heaven is “above” or that is, outside the Earth’s sphere. According to this theory, however, hell is placed above, since “beneath” to us is placed above us – hell thus being in a larger outermost sphere around the inner sphere of our habitation, and heaven being at the centre of both spheres. A dizzying thought even to comprehend.