Rabbi Yakov Haber
Before the parshas hamoa'dim, the description of the festivals, in parshas Emor, the Torah lists several mitzvos which do not seem to be connected (Emor 22:26-33). First, the Torah directs us to bring an animal as a korban only from the eighth day of its life and onward. Second, the Torah adjures us to not slaughter a cow and its calf on the same day. Following that the parsha describes the timeframe for consuming the korban toda: a day and a night. Many commentaries note, based on the Toras Kohanim, that the novelty of this section is that the intention during the processing of the korban should be to eat it in its designated time frame (see Rashi and Seforno). Fourth, the Torah directs us to keep (or: study) and perform all of the mitzvos. This is capped off with the commandment not to desecrate the Name of G-d and that G-d's name should be [or: "will be"] sanctified among the Jewish people. All of this is followed by G-d identifying Himself as the One who took us out of Egypt to be our G-d. What is the link between these seemingly diverse mitzvos?
The commentaries offer different suggestions, each with their own message. Seforno suggests that the connection is precise boundaries of time: the eighth day of the animal's life, not slaughtering cow and calf on the same day, and eating the korban toda in its designated time. After the Torah prohibits bringing animals with defects as korbanos, the Torah indicates precise times for the korbanos and their preparation. The common theme is the striving for perfection as indicated by the precise rules of perfection in the animal and the precise time rules for their offering. By serving G-d in this way, the one who offers the sacrifice inculcates the central message of trying to emulate G-d's perfection in all of his actions. The Torah then concludes with the general message to be derived not to desecrate the Divine Name through defective activities not appropriate for one striving to emulate Divine perfection. The reward for that will be that G-d will miraculously protect and elevate His beloved nation and His name will be sanctified through that (see Ki Tissa 34:10).
Netziv, in his Ha'ameik Davar, explains that this entire section serves as an introduction to the parshas hamo'adim, which immediately follows. Indeed, these introductory pesukim are read on the festivals Pesach and Sukkos indicating their connection. But how are these commandments connected to the festivals? Upon deeper reflection, explains the Netziv, each of them is. Because some of his discussion is somewhat technical, we describe here only some of the Netziv's analysis. A korban toda is normally brought out of a sense of thanksgiving to Hashem for some specific miraculous salvation which the one offering the korban experienced. However, the Netziv proves from the prophet Amos and elsewhere that korbanos toda were offered regularly on Sukkos as forms of supplication for rain. Elsewhere (Tzav 7:13) Netziv explains that toda offerings with 40 loaves of bread to consume theoretically should have more, not less, time within which to eat them. But, surprisingly, an ordinary korban sh'lamim must be consumed in two days and a night whereas the toda must be consumed within a day and a night! The Netziv explains that in order to assure that the contents of the offering be consumed on time, the offerer would certainly invite many guests. This will serve as a proper forum for him to publicly thank G-d, the Performer of the miraculous salvation. As Hallel states: "l'cha ezbach zevach toda...negda na l'chol 'amo" - "I will offer a toda sacrifice to You ... in the presence of His entire nation". One might have thought that a korban toda being brought in anticipation of rain should not have this restriction since it is not a classic thanksgiving offering. Therefore the Torah stresses that this toda too should be consumed in one day and a night. Finally, the Torah concludes that one should not desecrate the Name of G-d through frivolous behavior during the festivals. And one should sanctify G-d's name in public through communal prayers offered during the holiday. Netziv and Ramban both teach that this is one meaning of mikra kodesh (23:2), a holy convocation.
The concept of thanksgiving is a major theme in Judaism. The word hoda'a has a dual meaning. L'hodos means to admit. L'hodos also means to thank. The first step to thanking is admission and recognition of the true benefactor. Ramban (end of Bo) makes the following monumental statement summarizing the purpose of the Exodus of Egypt with its attendant miracles: "The Exalted G-d has no need for the lower world except that Man should know and yode to the G-d who created him. The purpose of elevating the voice in prayers and the purpose of synagogues and the merit of public prayer is that people should have a place to gather and yodu to G-d that he created them and formed them and they should publicize this and state before Him: 'We are your creations!'"
Netziv provides for us a new insight into thanking HKB"H: anticipatory thanks. By offering a korban toda, in effect thanking G-d in advance for the rain that He will bring, we gain Divine favor to send the rain. The exact parameters of when it is appropriate to thank Hashem in advance, I leave for further study. But minimally we learn from the Netziv's words the power of appreciating and thanking Hashem for all He has done for us. Rav Shalom Arush shlit"a in his eye-opening work Sh'arav b'Todah stresses the often overlooked avoda of thanking HKB"H. He recounts many stories of those who merited salvation not necessarily through heartfelt prayer but through heartfelt thanks for all the gifts that Hashem granted them. He presents a fascinating analysis based on Kabbala sources. Tefilla can sometimes be refused as prosecuting angels above will present negative reasons to deny the request. But thanks and appreciation to G-d goes unchallenged by the angels. One can prosecute against hearing a request, but how can one prosecute against a thank you! Therefore it has a tremendous ability to gain Divine favor.
As we approach Yom Ha'atzmaut, celebrating the foundation of the State of Israel, may we all take some time out, however we celebrate it, to thank HKB"H for all the gifts he has granted us, and specifically for rebuilding the Holy Land physically and economically to a large extent, returning Jewish sovereignty to large parts of it, returning over six million (kein yirbu) of its children onto it, and, most importantly, for orchestrating the enormous rebirth of Torah study and the observance of its commandments including the many mitzvos hat'luyos ba'aretz, the Land-dependent mitzvos. May we be zoche to see additional strengthening in sh'miras hamitzvos among all of our brethren and the re-establishment of a malchus based totally and unequivocally on the observance of Torah with the coming of the ge'ula sh'leima speedily in our days!
 I urge the interested reader to see the Netziv's words inside to see the whole picture.
 This, in turn, serves as the basis of birchas hagomeil absent the possibility currently of offering a toda.
 Compare to Ta'anis (23a) where Choni HaM'ageil offers a toda and supplicates G-d to stop the abundance of rain (brought about by his prayers!) threatening to flood Eretz Yisrael. Perhaps, though, the toda was offered for the rain which had already fallen.
 Indeed, Ashkenazic custom decreed the B'HaB fast days to atone for such behavior.
 I deliberately did not translate the word yode to allow for the dual meaning of admission and thanking. Both I think are inherent in Ramban's words.
 See Netziv that the lechem brought with the toda, symbolizing parnassa, was especially appropriate when praying for rain.
 Or even perhaps, for whatever reason, do not celebrate on this day. This is not the place for an expanded discussion on this topic. The point being presented here is thankfulness to G-d for the gifts He has granted us. This should transcend the debate over the religious celebration of this day.