The Imrei Emes, Rabbi Avraham Mordechai Alter of Ger, explained the purpose of drinking on Purim to his chasidim by means of a story: One time, the Baal Shem Tov foresaw that there was a terrible decree hanging over the Jewish people. He gathered some of his closest disciples and made a strange request. “I want you to go to this-and-this drunkard in this-and-this town,” he instructed them, “and wait until he sobers up. This will probably take a while, and you might have to use physical force to separate him from his wine. Once he is in a serious state of mind, ask him to pray that the decree be annulled.” The disciples were confused, but nonetheless immediately went to fulfill the Baal Shem Tov’s request. As predicted, it wasn’t easy, but eventually they succeeded.
Upon their return, one of the disciples could hardly contain his curiosity. “Rabbi,” he blurted out, “I don’t understand it. This man was the lowest of the low. He was literally rolling in the streets in puddles of mud. What power does he have that he can annul a decree?” The Baal Shem Tov explained that this Jewish drunkard had once painstakingly saved a lot of money. After he had amassed a large sum, he travelled to a faraway city to perform a certain sin. In the middle of his journey, however, he suddenly heard the sound of a woman sobbing. He stopped his wagon, climbed out and went over to investigate. “Why are you crying?” he inquired.Through heavy sobs the woman answered, “I am a widow and I have small orphans at home. There isn’t even a crumb to eat in my house. My poor children are going to die of hunger.” The Jew was overcome by tremendous compassion. Withdrawing the entire sum of money from his pocket, he handed it over to the poor woman. “This action,” continued the Baal Shem Tov, “caused a huge commotion up in Himmel.
A Yid who was on his way to sin had given away all his money! In Heaven it was decided that as a reward, the next thing this person asked for would immediately be fulfilled. But there was one problem: What if he asked for the geulah? The redemption couldn’t come before its proper time. It was therefore decreed that this Yid would be in a constantly inebriated state. That way, he would never be in the proper frame of mind to ask for anything.” The Imrei Emes concluded this story by saying: “Purim is an exceptionally holy day that is full of potential. We know that whatever a Yid davens for he will receive. Consequently, to ensure that no one would be able to properly pray for the geulah before its time, Purim was assigned as a day that one gets drunk.”