Why do we fast on the day before Purim?
The most obvious reason, is that this day is in commemoration of the three-day fast enacted by Esther, before she went to see Achashverosh. However, there are a number of issues raised by this approach.
Esther’s fast did not take place on the thirteenth of Adar, it took place in the middle of Nissan. Furthermore, the real fast of Esther was a three-day fast.
I would like to offer a suggestion of my own, in attempt to deal with these difficulties.
We find, near to the end of Hilchot Megillah, an extraordinary halacha in the Shulchan Aruch. The Mechaber tells us that if someone finds it very difficult fasting, rather than eat before hearing the megillah, it is preferable to read the megillah slightly earlier, as long as it is after plag hamincha.
What makes this approach so strange, is that regarding fast days – taanit Esther is looked upon as being one of the more lenient. Yet when it comes to the end of the fast, we are told that one must do whatever one can in order to avoid eating before the megillah. Even the Mishna Berurah who disputes this halacha with the mechaber, is also very strict about eating before the megillah reading.
The most obvious reason for this halacha, is based on the general rule that whenever an obligation has to be fulfilled, one must do it immediately, thus to begin a meal before the reading of the megillah would negate such a rule.
However, I think that there is a further reason as to why we must not eat before the reading of megillah, and by dealing with this issue, we will also understand why we fast on the day before Purim.
The Gemara tells us that in the story of Purim, all the components that would lead to the ultimate salvation of the Jewish people were in place before Haman came to power. The first three chapters of the megillah, inform us of how Esther became queen, and of how Mordechai had his name inscribed in the book of chronicles. It is only in the third chapter, having established that everything is in its place, that we are told that Haman came to power.
“Hakdamat terufah lemacah” is not a specific phenomenon to Purim, the message we are given by the talmud, is far fetching but true. The solution always precedes the problem, we just have to know how to apply the solution. In our case, the fact that Esther was queen would have meant nothing had she been ignored by the king. Similarly, the fact that Mordechai had once saved the life of the king, would have been of no consequence, had the king slept well on the night between the two feasts.
The solution was in place but it was only yad Hashem that ensured that it be applied effectively. What invoked yad Hashem? The three-day fast decreed by Esther. During these days, the assimilated Jews of Shushan, the Jews who had participated in the feast of Achashverosh, repented. They clothed themselves in sackloth and ashes, and turned to Hashem as a united people with a united cause.
The fast of Esther, the repentance of the people, is what made sure that when the medicine was taken it would indeed cure the people. The fast of Esther is not simply in commemoration of what happened then historically, it is an integral part of Purim. Indeed the gemara at the beginning of the masechet needs no proof as to why we could read the megillah on the thirteenth of Adar, since the fast of Esther is inherent within the definition of Purim. Without the fast there would be no Purim, it is the key to everything. When we fast before purim we are remembering the principle not the historical event, thus there is no need for a three-day fast.
To my mind, it is for this reason that the Shulchan Aruch ruled that there be no break between the end of the fast and the reading of the megillah. In order that we internalize the fact, that when we read the megillah we understand that the salvation is a direct result of the fasting and repenting.
Similarly, we can understand why a fast that in fact took place in Nissan has been juxtaposed to the day before Purim.
There is no time like the present to understand the depths of this message. When we truly believe that the solution lies with Hashem, when we truly turn to Hashem, then salvation will come.