Which is the most frustrating profession today? Sales. A study conducted several years ago in the United States attempted to discover the secret of success—why do some people survive and thrive in this profession while others find it so dismally unfulfilling? They found that the single most important factor is the ability to deal with the many small disappointments that crop up over the course of a day.

The sense of disappointment is one of the most painful feelings we can have. Many people spend years agonizing over one poor decision or lost opportunity. Surely all of us can remember at least one or two episodes that left us kicking ourselves with regret—why didn’t I choose differently?

The response to disappointment falls into two categories. Some choose to bemoan their sorry fate, or blame everyone and everything for their failures.

Then there are those who find little comfort in blame or excuses. The disappointment spurs them to action. They examine their behavior to find out what went wrong and what they can do differently. And these are the people who tend to be successful in sales and in the game of life.

This week we mark a positive outcome of an intense disappointment. It happened the first year after the Jews left Egypt. For the first time the Jewish people would bring the korban Pesach, the paschal offering, in the Mishkan (tabernacle), which had only been erected weeks earlier. The celebration was marred by tragedy—the two older sons of Aaron, Nadav and Avihu, hastened to enter the Mishkan at an inappropriate time and brought a fire to G-d. As a result, they died.

Two of their cousins arranged for their burial, and as a result they became impure due to contact with the dead—the most severe form of impurity. Their purification process was not yet complete when Pesach entered, and thus they lost the opportunity to bring the offering and join the celebration with the rest of the Jewish people.

At their first opportunity, the two cousins approached Moses with a complaint: “Why should we miss out?” They refused to give up the privilege of bringing a korban Pesach! Their demand reached the heavens and was accepted, and G-d handed down a ruling to institute a new mitzvah—Pesach Sheni, a second-chance Pesach to be celebrated a month later, on the 14^th of Iyar.

This is the message of Pesach Sheni—it’s never too late. As the previous Lubavitcher Rebbe, Rabbi Joseph I. Schneerson says, “It’s never too late. We can always make amends.”

The two nephews of Aaron missed their chance to do a mitzvah because they were engaged in a greater mitzvah, burying the dead. However, this knowledge did not comfort them. They would not give up on their strong desire to bring a korban Pesach, and in the end they were vindicated.

Throughout the generations, the Jewish people have suffered countless disappointments. There were many times when it seemed the Redemption was imminent but it did not materialize. To this day we are awaiting Moshiach and as of this writing we are still stuck in exile.

But witness the insistence and desperation of two men who lost the opportunity to fulfill one mitzvah, and in the end their persistence was rewarded. We have lost out on many more opportunities to bring a korban Pesach over the course of our exile. If so, shouldn’t we be storming the heavens, demanding that the Holy Temple be rebuilt? We must learn from them never to give up, to ask G-d again and again for the Redemption—and certainly we will celebrate Pesach Sheni in the rebuilt Holy Temple.