Ta'anit 9 - 15
Till the Last Jew Gets Home
In Eretz Yisrael Jews begin praying for rain by saying "Vetain tal u'matar livracha" in the ninth blessing of the shmone esrei on the seventh of the month of Cheshvan.
Why on this date and not Succot time when rain is already needed?
On Succot itself we don't pray for rain because the answer to such a prayer would prevent us from dwelling in the succah, and would be interpreted as a sign that Hashem rejects our efforts to serve him by fulfilling that mitzvah. But why don't we begin as soon as Succot is over?
Rabban Gamliel explains that we delay our prayer for rain in consideration for the Jew who has come to Jerusalem from the most distant point in Eretz Yisrael to fulfill the mitzvah of a pilgrimage to the Beit Hamikdash. We are concerned that he should be able to return home without getting caught in the rain. Since such a journey to a point near the Euphrates River could take up to fifteen days, we wait that amount of time before praying for rain.
This consideration would seem to be limited to the time when we had a Beit Hamikdash to which we were commanded to make a pilgrimage three times a year on the Festivals. But no distinction is made by the Talmud or the commentaries between then and now.
One of those commentaries, Rabbeinu Nissim ben Reuven (Ran), offers an interesting explanation.
This practice extends even into the period after the destruction of the Beit Hamikdash because it was the custom of Jews to continue coming to Jerusalem during the Festivals. (He even notes that in his time - about six hundred years ago - they were still doing so.) Out of consideration for these Jews who were perpetuating the spirit of the Beit Hamikdash pilgrimage, the prayer continued to be delayed so that they too could arrive home without getting caught in the rain.
Anyone who lives in Eretz Yisrael, especially Jerusalem, can testify that this custom of visiting Jerusalem and the site where the Beit Hamikdash stood on the Festivals is still very widely practiced.
The Heavenly Sign
The fast days legislated by our Sages in a season when there is no rain begin in the month of Cheshvan and end with the month of Nissan. The reason for not fasting beyond Nissan, says the mishna, is that rain which falls (in Eretz Yisrael) after the month of Nissan is the sign of a heavenly curse since it is counterproductive at such a late date.
As a source for this, the mishna cites the confrontation the Prophet Shmuel had with the Israelites after they demanded a king to rule them in his place. To demonstrate to them that Heaven disapproved of the manner in which they had made this demand he declared: "Today is the time of the wheat harvest and I shall call to Hashem and He shall deliver thunder and rain; thus shall you know and see how great is the evil in the eyes of Hashem which you have done to demand a king." (Samuel I 12:17)
Although the surface reading of our mishna would indicate that anytime rain falls after Nissan it is a cursed sign, the commentaries cite a statement in the Jerusalem Talmud (1:8) to the effect that this is so only if no rain had fallen previously; only then is rain after Nissan a blessing rather than a curse.
This distinction, points out Tosefot Yom Tov in his commentary on the mishna, is evident in the text of this mishna as it appears in the standard editions of the Mishnayot. In contrast to the text - "Nissan has passed and rain falls" - which appears in the standard editions of the Talmud, the text there reads "if Nissan has passed and rain has not fallen." Although both texts refer to rainfall after Nissan, the Mishnayot text indicates, like the Jerusalem Talmud, that the problem is only when rain has not previously fallen. As a parallel, Tosefot Yom Tov cites the mishna in Masechta Moed Katan (3:3) which distinguishes between plants which were watered before a holiday and those that weren't, in regard to the benefit they will derive from being watered during the intermediate days of the holiday.
We may suggest that there is even a hint in the biblical text to this distinction. The passage following Shmuel's statement (12:18) relates that the prophet called to Hashem "and Hashem delivered thunder and rain on that day." The stress on "that day" seems to signal that no rain had fallen before that day, and that is why it was considered a sign of Heavenly disfavor, which would not have been the case if rain had fallen before "that day."