The very first words of the Torah in Parshat Bereishis are,
"In the beginning Elokim created the heavens and the earth."
Rashi immediately jumps on the pasuk and brings down R. Yitzhak who says, "the Torah should have begun with 'this month shall be your first month,' it being the first Mitzvah Bnei Yisrael were commanded."
The fact that the Torah began with the words, "In the beginning Elokim created" is to declare the power of G-d's works to his People in order to give to them the inheritance of the Nations.
Thus should the nations of of the world say to Israel, "You are robbers, for you have taken by force of the seven nations," Israel can answer "all the earth belongs to G-d." He created it and gave it to us as an inheritance.
Rashi knew fully well that 1000 years after he had lived that the Land of Israel would once again come back to the Jewish People. He anticipated this happening 1000 years before it did. Clearly prophetic. He chose the very first words of the Torah to declare the land of Israel as the eternal inheritance of the Jewish People.
Yes, the word "Bereishis" begs to be expounded upon. Rashi says that the world was created for the sake of Torah which is called "Reishis of his Way".
The fact that Rashi makes these two points at the very beginning of the Torah highlights the importance of the Land of Israel as the Jewish People's eternal Homeland and the Torah its eternal Treasure.
The remaining of the Five Books of Moses can forward. Rashi felt it essential to point out the two most critical issues right off the bat - Israel and Torah. Two inseparable aspects of the Jewish People.
The Maharal in his Gur Aryeh asks of why Rashi brings down R. Yitzhak connecting Mitzvos to the Land of Israel.
What is the connection of Mitzvos to the Land?
The Maharal answers that most Mitzvos in the Torah are dependent upon the Land of Israel. Therefore Rashi felt obligated to connect Torah and the Land of Israel at the outset.
A famous Sifrei is brought down by the Ramban on Bereishis 26:5 ("Because Abraham obeyed my voice, and observed My Safeguards, My Commandments, My decrees and My Teachings") and quoted again by the Ramban in Vayikrah 18:25 and Devarim 11:18 which that the Mitzvos are intrinsic to the Land of Israel. Although most would say that the performance of all Mitzvos have much more value performed in the Land of Israel compared to the Exile, this Sifrei seems to imply that the the only real place where Mitzvos can be performed properly is in Israel.
This Sifrei makes it more understandable why Rashi felt compelled to connect the Mitzvos/Torah with the Land of Israel in the very first pasuk of the Torah. They are intertwined and inseparable. May the Torah and Mitzvos flourish in the Land of Israel and the World over today like never before in our .