Tehillim 119:33
הוֹרֵנִי יְהוָה, דֶּרֶךְ חֻקֶּיךָ וְאֶצְּרֶנָּה עֵקֶב
horeni HASHEM derech chukeicha ve'etzrena ekev
Teach me, O HASHEM, the way of Your statutes; and I will observe [guard] it step by step.
The term עקב (literally a heel) denotes an end point. A corresponding interpretation thus says: "I will observe it" because of what follows in "the end (עקב)." I will observe the mitzvot for the reward this brings.
A similar interpretation says, "I will observe it to the end" of my life.
Alternatively, "I will observe it to the utmost."
"I will observe it for itself." The reward for keeping the mitzvot will be in the very keeping of the mitzvot. As Chazal have taught, the reward of a mitzvah is the mitzvah itself (Avot 4:2).
The Midrash says, "Teach me, O Hashem, the way of Your statutes." What is "teach me"? David Hamelech said to the Almighty, "Do not tell me, here are the statutes before you, study them by yourself. Rather, You teach me! What is the "way"? You make a way for me! What is "I will observe it עקב"? Head the Torah "step (עקב) by step." Devote yourself to Torah study to the utmost! For if a man devoted himself to Torah study all his days, but then abandoned what was already in his possession, it is as if he had never devoted himself to Torah study. The same is true of all things. Compare it to an artisan who spent a long time making a lamp for his king, brought it to the palace, but then it broke in his hands. It is as if he had never labored at all!
- Me'am Lo'ez; Midrash
