והיה עקב תשמעון
Usually translated - and it shall be because you listen to these ...
Literal translation - and you listen to the heel
If you listen to even the lighter commands which a person usually treads on with their heel.
The One of Blessed Name gave Torah to Israel with 613 Mitzvot. And some of them are light and some are heavy. For there are Mitzvot which are light, where a person doesn’t pay them much attention, rather goes along with them under their heel, which is to say, they are light. [And about these light Mitzvot it is said] by them your servant is warned, in keeping them there is great reward [eikev rav] (Psalm 19).
Sefat Emet 5631:1
God created the world to be conjoined to creation by means of Adam until everything comes close to the One of Blessed Name. So the explanation of ‘you listen’ is that you should sensitize and internalise [muragash v’nshma] yourself to the enlightenment [haha’arah] which is in every thing, for there is Divine enlightenment in every thing, and this is the inner point. So the Children of Israel need to see all their deeds as a cleaving to the lifeforce of this point. And by means of this, the light continues and the understanding of God is in every thing. And this is ‘light Mitzvot’ - to cleave also to the regular things for by means of doing them everything becomes purely a reflection of Divine will.
And ‘Eikev’ this is the lowest step, and this is the ‘Eikev Rav’ and this is the aim and will of the Blessed One - for all creation to be joined one to the other until even the end and the lowest shall be drawn towards the first/highest [hareishit]... And this is the aspect of the fear of heaven [yirat shamayim] - to be continually in awe of the Blessed One, in every act small or large. And in the Talmud (Brachot 33b) on the verse What does God your Lord ask of you? Only to fear God and love God... (Deuteronomy 10:12), when it asks, ‘fearing God, how is this a little thing?! It’s called a little thing because for Moses it was a little [obvious] thing.’ [But don’t underestimate the importance of yirat shamayim.] Know that fear of God is the essential thing, it is the basis and the first step [hareishit]. In any event it’s the precursor of everything else mentioned in the passage; cleaving to God and loving God. Fear comes before everything and through it one also comes to love. And from this comes the idea that everything is in the hands of heaven, apart from the fear of heaven (Brachot 33b) for this is the step which is closest to Adam. And so it is light.