"After these events, G‑d's word came to Abram in a vision, saying, Fear not Abram, I am your shield. Your reward is very great." (Gen. 15:1)

The final reward for mitzvot is not in This World, it is reserved for the World to Come. (Kidushin 39b) Yet there is still another kind of reward in This World for doing mitzvot. Ben Azai teaches in the Mishna (Avot 4:2), "mitzvah goreret mitzvah" - "one mitzvah is a reward for another mitzvah". For example, sometimes G‑d grants one wealth after doing a mitzvah. But the money is not the real reward, that is reserved for the World to Come. The money is a gift from G‑d to enable one to do additional mitzvot. When one performs a mitzvah, G‑d provides the resources to do more mitzvot…

G‑d showers us with his beneficial influence and gives us all manner of plenty in This World in order that we may be engaged in Torah and mitzvot. When one performs a mitzvah, G‑d provides the resources to do more mitzvot. Thus, each mitzvah brings its eternal reward - plus the next mitzvah in This World which is the guaranteed source of our livelihood.

Abraham constantly kept G‑d's presence before him and cleaved to him in every possible way. This can be compared to a man who bears a shield in front of himself for his protection. The shield is securely fastened to his hand and arm, and he doesn't dare release it lest his enemies find him vulnerable. This explains the meaning of the verse "…Fear not Abram, I am your shield": since you have made Me your shield and have attached yourself to My Torah and mitzvot, your reward is therefore very great. Your adherence and enthusiasm in keeping My Torah and mitzvot is your shield and protection. You will be blessed also in This World with all you need to continue to engage in your service of G‑d.

[First published in B'Ohel Hatzadikim, Lech 5761]