I had a question from Taanis Daf 20a. The Gemara brings two possible gezairos shavos to prove that Moshe also made the sun stand still. Our Daf Yomi shiur here in Philadelphia was bothered by the fact that a gezairah shavah was used to prove a neis was performed, first because it is an unusual use of gezairah shavah and also what is the nafka mina l'halacha which is usually what a g"sh teaches (may not be a g"sh in the strict limud sense of the word).
However, learning the parsha this week compounds the question even more, as Rashi brings the Tanchuma which says that Moshe made the sun stand still "Ad ki bo shemesh" during the war with the Amalekim. If so, this is the mekor that Moshe made the sun stand still, why should the passuk use a gezairah shavah in Devarim by the Emorim?
Eric Haas, Philadelphia, PA, USA
I think Rashi (DH "Nakdimon") is addressing your concern by elaborating that "this is the way of the Pesukim to learn what is closed from that which is open with hints with words similar to its friend, and Gezeirah Shaveh is one of the thirteen Midos that was given to Moshe mi'Sinai." If Rashi were just trying to explain the concept of Gezeirah Shaveh, he probably should have done it more towards the beginning of Shas. It seems to me that he is directly saying that the Midah of Gezeirah Shaveh is also used to explain Pesukim. However, I am unsure if he understands that it is an actual Gezeirah Shaveh or not.
The Tanchuma seems to be another opinion, just as there are three different opinions in our Gemara.
All the best,
Yaakov Montrose