The Babylonian Talmud (“BT”) clearly held the Earth was flat. R. Azariah de Rossi, in his Me’or Enayim devotes more or less a chapter to understanding the view of the BT on this issue.

De Rossi explains that there a various passages in the BT which assume a flat earth. For instance, De Rossi quotes the BT Baba Basra “the world is like an exadera [three sides are closed] and the north side is open. When the sun reaches the nothwestern side, it bends back and goes above the sky.” De Rossi explains that “anybody who understands this passage correctly realizes that . . . the sun’s circuit is not from above to below . . . and they agree that the nightly darkness is not caused by the sun being at that time below the horizon . . . this is all calcluated on the basis that the earth is flat and that the heavens only cover it like a roof of the exadera.”

De Rossi after noting that this opinion is pervasive in the BT, it is based upon the understanding of some at the time the BT was complied. He explains, however, that if “the sages of blessed memory who believed that the world was flat . . . been informed of what has become known in our times, namely, how the Spaniards . . . discovered the New World in the Northern Hemisphere where the inhabitants have their rest opposite the place where we put our feet. And the same is true of the place under the equator and also beyond it to the south above and below. With one voice [the sages] would have acknowledged that the earth was spherical.”

This last line, of course, was in part why De’ Rossi was controversial. By claiming Hazal based some of their statements upon the science of the day and that had they been exposed to what we now know would have changed their minds was, and continues to be a touchy subject.

But to return to our topic at hand – the flat earth – De Rossi points out that although the BT held the earth was flat not everyone at the time agreed. Specifically, he notes that the Jerusalem Talmud as well as Berashis Rabba seem to imply the earth is round. Additionally, the Zohar states the earth is round. It is this last source, however, which is somewhat problematic. Assuming the BT held the earth was flat and that appears to have been the prevailing attitude, why then would the Zohar disagree. R. Jacob Emden used this passage in the Zohar as one of the many which points to a later dating of when the Zohar was written. R. Emden states succinctly “this opinion is not one shared by Hazal and instead comes from later science.” Thus, according to R. Emden, the fact the Zohar assumes the earth is round lends itself to the notion it could not have been written (at least this part) by R. Shimon bar Yochi.

R. Emden’s challenge of the Zohar was not left unrebutted. R. Moshe Kunits in his Ben Yochi which is devoted to rebutting R. Emden, attacks this statement of R. Emden. Although he attempts to refute R. Emden, one who is aware of the above discussion, realizes how hollow R. Kunits’ argument is. R. Kunits agrees that the BT assumes a flat earth, but then he cites the two sources which do go with the round earth -Jerusalem Talmud and Berashis Rabba. In essence, Kunits is merely regurgitating De Rossi’s sources. In fact, he cites De Rossi as being one who demonstrates that Hazal held the earth was in fact round. Of course, De Rossi’s only sources were the Zohar and the others cited by Kunits. Thus, in the end, Kunits’ arguments are circular. This fallacy is noted by R. Shlomo Yehudah Rappoport in his book to rebut Kunits – Nahlat Yehuda.

Finally, it appears that the idea of a flat earth persisted until at least the 18th century (and if the recently published book, Afeki Mayim, is an indication even until the 21st century). The person in the 18th century to follow this view is a rather surprising one in light of how knowledgable he supposedly was in secular wisdom (at least according to some). The Vilna Gaon is recorded as stating the earth must be flat in order to properly understand the verse in Job (38:13) “that it might take hold of the ends of the earth.”

Sources: De’ Rossi, Meor Einayim (ed. Weinberg) Imrei Binah, Section 1 chap. 11. Zohar, Vaikra, 10a; R. Jacob Emden, Mitpahat Sefarim; R. Shlomo Yehudah Rappoport, Nahlat Yehuda (Lemberg, 1873); R. Kunits, Ben Yochi. On the Vilna Gaon, see R. Y. Engel, Gilyoni HaShas, Shabbat, 74a and R. Reuven Margulies, Nitzozi Ohr on the Zohar cited above.