R’ Leibel Eiger explains that we see from this Chazal that despite the great merits that Sarah, Rachel, and Chanah surely had, those merits were in-and-of themselves not enough to warrant their being blessed with children. It was only because Hashem reviewed their case, so to speak, on Rosh HaShana, that they were zochos. The time of year is what made all the difference. We of course don’t have the same level of zechuyos that these tzidkaniyos had, but we do have the same opportunity to take advantage of this special, mesugal time period. The gates upstairs are open and things that a person couldn’t be zocheh to, no matter how great he/she is, are now possible to merit.
It’s been a short week with less time than usual, so I just want to pose a question on the parsha and leave it at that because I don't yet have a good answer to share. The theme of Parshas VaYeilech is the transition from the leadership of Moshe, whose life is coming to a close, to that of Yehoshua. We have Moshe giving a final speech to Bnei Yisrael, Moshe turning over the sefer Torah he completed to the Bnei Levi, Moshe giving a charge to Yehoshua to be strong, and in the middle and midst of all this we have the mitzvah of hakhel. Why give that mitzvah here? Why not discuss it in Parshas Shoftim, where the laws of the king are discussed, since it is the king (Ralbag interestingly writes that the kohen gadol or any nasi can do the reading) who reads the Torah, or maybe in Parshas Behar, where the laws of shemita appear, since hakhel is done right after the shemita year? Why stick it in the middle of our parsha, in the middle of Moshe turning over the reins (and the reign) to Yehoshua?