In our religious teachings we have a concept of זכות אבות, parental merit. This means that if we do not earn the heavenly rewards from Hashem by our own advantage, if our parents or previous ancestors were worthy people their merit benefits us as well.
Our Sidra starts with the words: וְהָיָה עֵקֶב תִּשְׁמְעוּן, “This will be the reward when you hearken…” to the laws and the Mitzvot commanded you, Hashem will keep, אֶת הַבְּרִית וְאֶת הַחֶסֶד אֲשֶׁר נִשְׁבַּע לַאֲבֹתֶיךָ: “…He will keep for you the covenant…which he swore to your forefathers.” (Deut. 7,12)
This means if the Jews will adhere to the Torah and the obligations it places on us, then Hashem will keep the promise made to our forefathers directly with us: לך, for you. This implies there will be no need for זכות אבות, for the merit of our parents or forefather. We will have earned the covenant with Hashem ourselves, on our own merit.
This indeed is a worthy promise and it places on our shoulders the responsibility to secure this promise on our own directly from Hashem.