Devarim/Deuteronomy 7:12 — first verse of the portion Eikev*
And if you do [v’haya eikev]* obey these rules and observe them faithfully, the LORD your God will maintain for you the gracious covenant that He made on oath with your fathers: — JPS/Plaut
“And it shall come about in consequence [v’haya eikev]* of your heeding these laws when you keep and do them, that the LORD your God will keep the covenant and the faith for you that he swore to your fathers….” — Alter
This shall be the reward [v’haya eikev]* when you hearken to these ordinances, and you observe and perform them; HASHEM, your God, will safeguard for you the covenant and the kindness that he swore to your forefathers. — Stone
*Plaut (The Torah: A Modern Commentary):
…[Eikev], literally, “on the heel of,” i.e., in consequence of your obeisance.#
in consequence of — The relatively unusual Hebrew preposition ‘eqev literally means “on the heel[s] of.”#
[Eikev] — the reward. The translation follows Onkelos and R’Saadyah Gaon, and is similar to that of Ibn Ezra. Ramban renders because [you will hearken…].
Midrashically, the word [eikev], which also means heel, alludes to the sort of commandments that people may regard as relatively unimportant, so they tend figuratively to “tread on them with their heels.” Thus, the Torah assures Israel that if they are careful to observe even these neglected commandments, they can be certain that God will reward them with His covenant and kindness (Rashi).#
From the concordance: There is one more use of eikev in Devarim/Deuteronomy, 8:20; two are in Genesis/Breishit — 22:18 and 26:5, both in reference to Abraham’s faithfulness (the former follows the Akedah); and one in Numbers/Bamidbar, 14:24, in reference to Caleb’s faithfulness.