By the Grace of G-d
11th of Shevat, 5720
Brooklyn, N. Y.
...With regard to your question whether you are obliged to accept the opinion which, you write, is expressed in our Torah to the effort that the earth is flat, I am not aware of such a statement in the Torah. On the contrary, we have a clear statement diametrically different which, is found in the Zohar, part 3, page 10a, to the effect that “the earth spins around as a globe, and that creatures differ from one another by reason of climate, and there are parts on the earth where there is light, while there is darkness in others, it is day for some and night for others, and there is a place where there is always light throughout the year except for a brief period of darkness.” It is noteworthy that hundreds of years after this was written in the Zohar, debates were still carried on in outstanding universities of Europe, in Paris, and others, as to whether the earth had four corners, rests on pillars, etc. If one still wants additional proof that the Torah is from Heaven, the above may serve as scientifically irrefutable proof.
