In the battle of the four kings versus the five kings this week, Lot is captured. We are told that ‘the one who escaped from the war’ comes and tells Avraham what has happened, so he should go and save Lot (14;13). This ‘escaped one’ is Og, later to be King of Bashan. Years later,Og leads his nation out to war against Bnei Yisrael in the desert, who are on their way into Eretz Yisroel, under the leadership of Moshe Rabeinu. The pasuk (Bamidbar 21;34) tells us that Moshe was scared of Og. Why; HaShem had battered Egypt’s might, He could definitely beat Og? As Rashi tells us, Moshe was not scared of Og’s physical might, but rather of the merit of this mitzvah that Og did in informing Avraham about the battle and Lot’s capture. In fact, some say that it was in the merit if this mitzvah that Og lived so long – from the time of Avraham Avinu to Moshe Rabeinu. We can see the great reward for even one mitzvah here and how precious each mitzvah is. As Rav Dessler explains, the phrase ‘reward for mitzvah is not in this world’ means that all the physical pleasures and happiness of everyone in the history of the world put together cannot match the real spiritual reward for a mitzvah. The great reward of Og is just a glimpse of how tremendous one mitzvah is.