Parshas Bhar

One of the most famous questions in Rashi is in this weeks parsha, "Ma inyan shmitta aitzel har sinai" The torah starts the laws of shmitta with a introduction of "Bhar sinai" Rashi wants to know what is the significance that this mitzva was said at mount sinai. Rashi answers just like all the laws and applications of shmitta are taught in this parsha, at sinai, so to all the laws and applications of all the torah was taught at sinai. The answer still needs clarification, why is it that this mitzva was chosen to teach us this rule (that all mitzvas in their entirety were taught at sinai)? Why couldn't the torah teach it by the laws of kashrus for example?
The answer to all this lies in one word/concept- emunah - complete trust and faith in Hashem. When the yidden were at Har Sinai they got to the point where they saw Hashem as clear as day. As much as one believes in something it doesn't compare to seeing that thing. At that moment of Kabbolas Hatorah the revelation was so awesome that klal yisroel knew that Hashem is one and his name is one. Never in history was it that clear, that we actually saw and heard Hashem.
The forty years klal yisroel spent in the desert the main goal was to perfect this trust that even if they don't see Hashem they should fully trust in him. The Navi calls it a chesed that we followed Hashem blindly through the wilderness, with complete faith. (If one studies the problems encountered in the forty years they all are in some form related to lack of emunah). All this was in preparation for the ultimate goal of living in G-ds land totally immersed in faith of Hashem.
The posak states "When you come into the land which i give you, then shall the land keep a shabbos unto G-d. Six years you shall plow...... And in the seventh year there shall be a shabbos." R' Chaim Kanievsky in his sefer Tayma D'mikra points out that we know that while the Jews were conquering and dividing the land they didn't keep shmitta. It took twenty one years from when we entered Eretz Yisroel until we kept our first shmitta. He raises the question why does the Torah state "When you come into the land....." this wasn't true for many years. He explains it beautifully with a Medrash that says Hashem made a condition with Moshe that the jews will get the land only if they maintain the laws of shmitta. (That is how it actually played out as we see in the tochacha- curses in bechukosai chapter 26;34) That is what the posak means "When you come into the land, you must agree to these laws". Shmitta is more then just giving the land a rest. It shows complete faith in Hashem that even in a year when you don't touch your field Hashem is the one that's feeding you. This is why these laws were a prerequisite to living in Eretz Yisroel. For living in Hashem's land one must realize this and put his complete trust in him. Even more, everyone that knows anything about fields will tell you that it's not good to use your field year in and year out for it weakens the ground and it doesn't produce as it should. Yet the Medrash says that when the torah says that "Six years you shall plow..." it is to be taken literally. Hashem promised us that if you plow your field for six years and rest it on my time table- every seventh year, then it will be blessed so that not just the seventh year are you showing trust in him, but every year that you don't give the fields a rest you are showing complete faith in his Torah.
This is the juxtaposition between shmitta and Har Sinai. Just like the giving of the Torah was with complete faith in Hashem so to the goal of shmitta is to achieve complete faith in Hashem.