1) THE PRAYER FOR RAIN IN THE SHEMONEH ESREH
QUESTION: The Mishnah asks, "From when do we recite the prayer of Gevuros Geshamim," and proceeds to mention the day on which we begin to recite that prayer. The Gemara asks why the Mishnah assumes that there is an obligation to recite such a prayer, such that it asks "from when do we recite" it. The Gemara answers that the obligation to recite a prayer for rain is taught by the Mishnah in Rosh Hashanah (16a) which states that on Sukos the world is judged for rain. If there is a judgment for rain, it is obvious that a prayer of appeasement ("Hazkarah") for rain must be recited. Therefore, the Mishnah here asks from when this prayer must be recited.
Why, though, is the judgment for rain on Sukos grounds for reciting a prayer for rain at that time? The Mishnah in Rosh Hashanah also says that the world is judged for its crops on Pesach and for its fruits on Shavuos, but no prayers are recited for those items on those festivals. Why is there a greater necessity to recite a prayer of appeasement in the Shemoneh Esreh on Sukos for rain than to recite a prayer of appeasement for crops or for fruit on Pesach or Shavuos?
ANSWERS:
(a) On Pesach and Shavuos, as well as during the rest of the year, we ask Hash-m to "bless for us this year and all of its produce that they should be good for us, and place Your blessing on the face of the earth..." ("Barech Aleinu" in Shemoneh Esreh). In this blessing, we acknowledge that all produce comes from Hash-m, and thus it is not necessary to mention it in a prayer of appeasement as well.
In contrast, we refrain from asking Hash-m to send rain on (and immediately after) Sukos. Therefore, it is necessary to mention at least a prayer of appeasement for rain on (or immediately after) Sukos. We do not ask for rain on Sukos because rain during the festival is an ominous sign (28b). We do not ask for rain immediately after the festival because, in the times of the Beis ha'Mikdash, rain immediately after the festival would complicate the return home of those who came to Yerushalayim from afar (Ta'anis 4b). Therefore, it is necessary to say a prayer of appeasement (Hazkarah) for rain.
(b) The Gemara in Rosh Hashanah (16a) explains that on each day of judgment, the Torah bids us to perform acts of appeasement. On Pesach, the act of appeasement is the offering of the Korban ha'Omer. On Shavuos, the act of appeasement is the bringing of Bikurim. These two acts of appeasement are done in the Beis ha'Mikdash. On Sukos, the Torah describes two acts of appeasement for rain. The first act of appeasement is the Nisuch ha'Mayim, the water libation, which is performed in the Beis ha'Mikdash. The second act of appeasement is the Mitzvah of holding the Arba'as ha'Minim, which need large amounts of water to grow (Ta'anis 2b). This act of appeasement is done not only in the Beis ha'Mikdash but by every Jew in every location. Since every person performs an act of appeasement, it stands to reason that every person should make a mention of appeasement for rain in his Shemoneh Esreh. On the other festivals, when the act of appeasement is done only in the Beis ha'Mikdash, individuals do not have to make any mention of appeasement in their Shemoneh Esreh.
Why is there no public act of appeasement done on Pesach and Shavuos, as there is on Sukos? Perhaps rain is considered a more important commodity than crops and fruits, because the crops and fruits themselves grow only as a result of the rain. Therefore, the judgment on Sukos is the primary judgment while the judgments on Pesach and Shavuos are secondary, and that is why a special prayer of appeasement for rain is recited in the Shemoneh Esreh. (M. Kornfeld)
2) AGADAH: THE "GEVURAH" DEMONSTRATED BY RAIN
QUESTION: The Gemara says that the prayer for rain is called "Gevuros Geshamim" because the rains demonstrate the Gevurah (might) of Hash-m. In what way does rain, more than anything else, demonstrate the might of Hash-m?
ANSWERS:
(a) The MESHECH CHOCHMAH (Devarim 16:2) cites the Yerushalmi (end of Avodah Zarah 3:1) which says that although idolaters believe that their idols have power over the world, they admit that their idols have no power over the seas. The Meshech Chochmah says that in the same vein they admit that their idols have no power over water in general. For this reason, the Gemara in Sanhedrin (67b) says that water has the ability to nullify the power of Keshafim (sorcery). (Similarly, the Mishnah in Kelim (17:13) says that anything which comes from the sea cannot become Tamei.)
Similarly, the idolaters admit that their gods have no power over rain. As the verse in Yirmeyahu (14:22) implies, no idolater believes that his idol can bring rain. Since rain demonstrates the unique and unparalleled power of Hash-m as acknowledged by everyone, and which no one attempts to attribute to any other entity, the Mishnah refers to the prayer for rain as "Gevuros Geshamim."
However, several sources seem to contradict the Meshech Chochmah's assertion that the idolaters admit that their gods have no power over the sea, water, or rain. According to the assertion of the Meshech Chochmah, why did the shipmates of Yonah pray to their various gods to stop the storm at sea if they knew that their gods have no power over water? Also, the Gemara in Avodah Zarah (55a) relates that a certain idol visited people in their dreams and told them that if they sacrifice an offering to it, it will bring rain to them. (They offered a sacrifice and it indeed rained.) It is evident that the idolaters do believe that their idols have control over the sea and rain.
Perhaps the Meshech Chochmah understands that while the idolaters admit that their gods have no power over the sea and rain, they believe that sometimes their idols can persuade the true G-d to manipulate the sea or rain. They know that their gods have no permanent or independent power over water.
The Meshech Chochmah's assertion may explain why the Torah states that when the Jewish people follow the will of Hash-m, He provides rain in ample supply and at appropriate times (Devarim 11:14), and, conversely, when the Jewish people do not follow the will of Hash-m, He withholds the rains (Devarim 11:17). Since the rain is a clear indication of Hash-m's power, it is an appropriate way to demonstrate the reward for following (or punishment for defying) the will of Hash-m.
The Gemara here says that the keys to rain, childbirth, and Techiyas ha'Mesim are in the hands of no one but Hash-m. The RA'AVAN (at the end of his commentary to Maseches Berachos, #204) writes that childbirth and Techiyas ha'Mesim, like rain, demonstrate the power of Hash-m. For this reason, they are also mentioned in the blessing of Hash-m's Gevurah in the Shemoneh Esreh ("Atah Gibor..."). Following the Meshech Chochmah's approach, we may suggest that no idolater believes that his god has power over childbirth and Techiyas ha'Mesim. Since no one else claims to have the power of childbirth and Techiyas ha'Mesim, these things are also referred to as the Gevuros of Hash-m.
(b) The VILNA GA'ON (Aderes Eliyahu, end of the first verse in v'Zos ha'Berachah, Mahadura 2) suggests a different approach. He explains that the "four keys" refer to acts that defy nature. According to the laws of physics, it is impossible for the dead to be resurrected. Similarly, rainfall (and weather in general) follows no natural physical, predictable laws. It is not like sunrise and sunset or the motions of the planets and celestial bodies which can be predicted thousands of years in advance. In this sense, rainfall is "supernatural" and demonstrates the presence of the Creator more than any other event. Since it constitutes a clear demonstration of Hash-m's might, it is referred to as "Gevuros Geshamim."
The BEN YEHOYADA here (DH Sheloshah) follows a similar approach. He adds that the "agents" to whom all of the keys of the world are entrusted, with the exception of the keys to rain, childbirth, and Techiyas ha'Mesim, are none other than the forces of nature.
(c) In BENAYAHU (beginning of 7a), the Ben Yehoyada suggests another approach. As the Gemara says, rain is considered greater than the resurrection of the dead because it is beneficial not only to the righteous but also to the wicked.
The Mishnah states, "Who is the mighty person (Gibor)? One who conquers his will" (Avos 4:1). The only acts describable as "difficult" for the Creator, as it were, are acts through which He conquers His will and shows generosity even when it is not deserved. This is what the Gemara in Pesachim (118a) means when it states that providing sustenance for every person is as difficult for Hash-m as the Splitting of the Sea. The Splitting of the Sea was "difficult" for Hash-m because He performed the miracle even for the sinners of the Jewish people, as the Midrash says: "The idol of Michah passed through the sea" (Shemos Rabah 41:1). Since the evildoers were not deserving of the miracle, the act was considered "difficult." Similarly, Hash-m provides sustenance -- through rain -- for all people regardless of whether they deserve it or not. In this sense, it is fitting to refer to rain as the "might of Hash-m."
(d) As mentioned earlier, in the passage of "v'Hayah Im Shamo'a" (Devarim 11:14-17) the Torah teaches that there is earthly reward and punishment for the acts we perform specifically in Eretz Yisrael. Eretz Yisrael lacks natural, self-replenishing water sources (in contrast to other places, such as Egypt). If we fail to appreciate Hash-m's benevolence and do not follow His will, He will remind us of our absolute reliance on Him by holding back the rains (as He did in the times of Eliyahu and Achav).
In this respect, rain (or the lack of it) reminds us to trust in Hash-m and to turn to Him in prayer. It also reminds us of Hash-m's constant presence and supervision by showing Divine retribution in a direct manner of cause and effect. Since rain reminds us of Hash-m's presence and omnipotence, it is appropriate to refer to it as the "might of Hash-m." (M. Kornfeld)
(Although these four approaches appear to differ from each other, a deeper analysis makes it evident that they are complementary. They reflect four perspectives of the same concept.)

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