The Special Merit of Piety in Eretz Yisroel
והיה עקב תשמעון את המשפטים האלה ושמרתם ועשיתם אתם ושמר ה’ אלקיך לך את הברית ואת החסד אשר נשבע לאבתיך, ואהבך וברכך והרבך וברך פרי בטנך ופרי אדמתך דגנך ותירשך ויצהרך שגר אלפיך ועשרת צאנך על האדמה אשר נשבע לאבתיך לתת לך, ברוך תהיה מכל העמים לא יהיה בך עקר ועקרה ובבהמתך, והסיר ה’ ממך כל חלי וכל מדוי מצרים הרעים אשר ידעת לא ישמם בך ונתנם בכל שנאיך
And it will come to pass, If you shall listen to these commandments, and keep them, and do them, that Hashem your G-d shall keep with you the covenant and the mercy which He swore unto your fathers, and He will love you and bless you and multiply you. He will also bless your offspring as well as the fruit of your land, your corn, wine and oil, and increase of your kine and the young of your flock, in the land which He swore to your forefathers to give to you. You shall be blessed above all peoples; there shall be no barren male or female among you, or among your cattle. And Hashem will remove from you all sickness and He will put none of the horrible diseases of Egypt which you recognize, upon you, rather He will place them upon your enemies.
Rashi interprets the verses in accordance with the words of the Medrash Tanchuma. The word “עקב” is derived from the root word meaning “heel” and thus the pasuk is stating that when one takes care to perform the smallest of the mitzvos that one might ordinarily stamp down with their feet, then he will receive the blessings from G-d as enumerated in the verses that follow. The words of Rashi need clarification. What caused Rashi to understand that the verse speaks only of the “small,” i.e., easy mitzvos? Additionally, why is there such grand reward given for keeping the smallest mitzvos that the Torah should dedicate an entire section to it?
The Sifsei Chachamim  answers that Rashi’s intent is not exclusively the “small mitzvos.” But rather, Rashi means that if one carries out even the small mitzvos, then he will undoubtedly keep the more essential ones. Thus, this section is another of those enumerating blessings given when we perform the entire body of mitzvos correctly.
The Ramban  does seem to accept that Rashi sees the pasuk as referring only to the minor mitzvos. The previous Parsha (Va’eschanan) ends with the verse, אשר אנכי מצוך היום לעשותם – which I commanded you today to do them. Rashi brings the words of our Sages : “היום לעשותם” – today you are commanded to fulfill (the mitzvos), and tomorrow, in the world to come, you will receive your reward.
Our sages teach us  that שכר מצוה בהאי עלמא ליכא – reward for mitzvos is not received in this world; rather one obtains payment in the world to come. The reason for this, as explained by Rav Dessler , is that all the physical pleasures of this world that have been experienced by the total world population in the past, present,and future will still be insufficient to fully reward even one mitzvah. It is therefore not possible to repay someone a material reward for fulfilling mitzvos.
However, the Maharsha  tells us that reward for a “hiddur mitzvah” (beautification of a mitzvah), is received even in this world. Going above and beyond the minimum requirement of the fulfilment of the mitzvah is repaid even in this world. It is offered as a sort of “extra credit.” Just as the person who fulfilled the mitzvah did more than asked of him, he too is rewarded with “more.” Not only does he merit a portion in the next world, he will also benefit in the present physical world.
The Gemara states , “A person should always live in the Land of Israel. For one who lives in the Land of Israel, is as if he has a G-d, and an individual who lives outside the land of Israel, it is as if he does not have a G-d.” The Ben Yehoyada  explains with an introduction. The law is that mitzvos need intent  as it is written , היום הזה ה’ אלוקיך מצוך לעשות את החקים האלה ואת המשפטים ושמרת ועשית אותם בכל לבבך ובכל נפשך – This day Hashem your G-d commanded you to do these statutes and ordinances, therefore you shall do them with all your heart and with all your soul. “Heart and soul,” mentioned in the verse indicate intent and concentration.
We know that we are commanded to do mitzvos with intent, but we were not commanded to be extra scrupulous. Anything that we do out of extra piety may be commendable, but it cannot be said that it is done with the intent to fulfill G-d’s commandment, because G-d’s commandment does not incude the “extra.” As such, all “extra credit” mitzvos are somewhat lacking; by the mere fact that there cannot be true intent in doing them solely for the sake of Hashem’s commandment.
However G-d commanded that we be “extra” holy in the Land of Israel. As it is written at the end of Parsahas Acharei :
“you shall keep my mitzvos and my laws, and you shall not do any of these atrocities etc. for all these abominations the men of the land that have preceded you have done, and consequently they have defiled the land. That the land not also spew you out, when you defile it, as it ejected out the nation that was there before you….. Therefore shall you keep my charge, that you do not do any of these abominable customs, which were done before you, and that you defile not yourselves within, I am the Lord your G-d.”
The Gemara  deduces from the words, “therefore shall you keep my charge,” that we must be over-vigilant in keeping mitzvos and decrees to make sure we do not falter. Thus we see the Torah commands us that, in Eretz Yisroel, mitzvos should be done out of piousness and with the intent that Hashem commanded us to do so.
Now with this preface, the Ben Yehoyada says that the Gemara’s intent in saying, “one who lives in the Land of Israel is as if he has a G-d,” actually means, as if he has a G-d that commanded him even to do go the extra mile; as opposed to one who lives outside of Israel, that he does not have a commandment from G-d to be overly pious. Our Rabbis also say  that every four cubits one walks in Eretz Yisroel is, in itself, a Mitzvah. Eikev is the acronym for “Kaddesh Atzmecha B’mutter” – sanctify yourself even with things that are truly permitted.
We can perhaps now explain Rashi. He questioned how the Torah can promise earthly rewards for mitzvos. We know that we do not receive rewards in this world. He therefore explained that we are referring to one who does the smallest of the mitzvos, hinted in the acronym of the word Eikev; meaning one who does a Hiddur Mitzvah or a pious deed not explicitly required by the Torah. The Maharsha mentioned above declares that, for such acts, one does receive an earthly reward. Rashi continues that these mitzvos receive true reward on this world only if done in the Land of Israel.
What is meant by Rashi’s words, “mitzvos one might ordinarily stamp down with their feet,” is mitzvos performed while treading (stamping with one’s feet) on the holy, sacred ground of the land of Israel. Only in the Holy Land can the extra steps taken in performing mitzvos count as full mitzvos themselves and thereby merit an earthly reward.
A word of caution: the above is not a reason for us living in the Diaspora to despair or become less scrupulous in observance of mitzvos or even to shun performing those deeds that are so to speak “extra credit” just because we cannot gain an earthly reward for them. On the contrary, our sages teach us  that we should view ourselves as servants who serve their master without any ulterior motive of ever receiving compensation.
 Shabbethai ben Joseph Bass 1641-1718, Sifsei Chachamim is a supercommentary on Rashi’s commentary
 Nahmanides, also known as Rabbi Moses ben Naḥman and by his acronym Ramban 1194–1270
 Tractate Eiruvin 22A
 Tractate Kidushin 39B
 Rabbi Eliyahu Dessler 1892 – 30 December 1953, see Michtav meEliyahu.
 Rabbi Shmuel Eidels 1555 – 1631, see Maharsha Sotah 14A
 Tractate Kesubos 110B
 Rabbi Yoseph Chaim of Baghdad 1835-1909
 This is a dispute in the Gemara (Pesachim 114B). The Braisah holds that intent is not required and Reb Yossi holds it is required. The Rishonim argue as to which opinion we follow. Rashi and the Rambam hold that in order to fulfill a Mitzvah we need intent. The Rashba Tosofos and the Ran are of the opinion that intent is not necessary. The Shulchan Aruch Ohr Hachaim 60:4 rules that we do need intent to fulfill mitzvos.
 Deuteronomy 26:16
 Leviticus 18:25-30
 Tractate Yevamos 21A
 See tractate Kesubos 111A
 Tractate Avos 1:3