Comentario sobre Deuteronómio 4:40

ושמרת את חקיו, Once you have understood all this you will naturally observe all of G’d’s statutes. Jeremiah 10,7 already expressed this as a given when he asked (rhetorically) מי לא ייראך מלך הגוים, “who would not be in awe of You, King of the nations?”

נתן לך כל הימים, "which He gives to you for all time." Seeing that Moses told the people to observe the Torah in order to enjoy long life, he was afraid that the people would interpret that by observing the commandments of the Torah G'd would lengthen their lifespan on earth. As a result of such reasoning the people might also argue that this was proof that just as man's life on earth is limited in time (compare Job 14,5 "his days are determined, You know the number of his months"), so possession of the Holy Land would also be subject to limitations in time. Moses therefore corrects any such impression by going on record that a) G'd would add years to the people's lives if they observed the Torah, and b) assuring them that G'd's gift of the land to the Jewish people is a gift in perpetuity. It follows that when he mentioned "in order that you will have a long life on the earth, etc," Moses meant that they would not die prematurely, just as we have been told in Deut. 11,21. As to the land itself, it will remain Israel's forever.

V. 40. ושמרת את חקיו וגו׳. Dieses dein ganzes Wissen von Gott soll aber die einzige Wirkung haben, dass du in dieser gotterfüllten Welt, in welcher Sein Wille überall gebietet und Seinem Willen alles dient, auch nur das eine Anliegen kennst: seine הקים und מצות, mit welchen Er all deinem Wollen "Schranke" und "Aufgabe" gesetzt, gewissenhaft erfüllest, אשר ייטב לך, womit allein du dein und deiner Kinder Heil gewinnen kannst, ולמען תאריך, und wovon allein die Dauer deines Bleibens in dem Lande bedingt ist, das Gott dir für alle Zeiten gibt, das für ewige Zeiten das Land deiner Bestimmung bleibt, das du aber immer nur so lange innehaben wirst, als du dieser Bestimmung dich treu erweisest.

ואת מצותיו אשר אנכי מצוך היום, כל הימים, the reason you will be observing these laws for all time is that the religion will not be renewed or altered, ever.