The universe was in fact created out of the Hebrew alphabet. Adam and Eve spoke Hebrew. The first tablets were in ketav 'asshuri and the second in ketav `Ivri.
How could a rabbi know?
They can only go back to proto Sinaitic and forward from Egyptian Heiroglyphics to ascertain what languages Moses knew.
God either etched the second set in a language Moses didn’t know or in a language Moses knew so he could then carry that language over to the written Torah.
No rabbinical status or learning is needed to figure this out, nor to figure out that Masoretic Text, Aramaic Hebrew or Paleo Hebrre were around in Moses’time, but I guess some rabbi could engage in conjecture.