Shalom Aleichem. Today we are learning Chapter Reish Chaf Gimmel, 223. The discussion addresses a very practical question: what is the status of matzah that has been kept from the previous year? Can it be used the following Pesach?
The Rebbe responds that it is obvious that there is no issue, and that matzah from the previous year may be used. First, the Rebbe points out the simple reality that the matzah remains fit for human consumption. Practically speaking, it does not undergo a significant change over time, and therefore there is no reason to disqualify it.
The Rebbe then brings a proof from the halacha of eiruv chatzeros. When multiple people share a common courtyard or space, the Sages instituted that one must establish an eiruv in order to permit carrying. This is done by placing food—such as bread or matzah—in one home, symbolizing that all residents share a common dwelling.
The Alter Rebbe records a custom that on Erev Pesach, people would collect flour from each household and bake a single matzah, which would then serve as the eiruv for the entire year. The advantage of using matzah was that it avoided any concern of chametz throughout Pesach.
This practice demonstrates that the matzah remains valid and usable for the entire year, since it continues to serve as the basis of the eiruv even until the following Erev Pesach.
A question was raised: perhaps this only proves validity for up to one year, from Erev Pesach to Erev Pesach, but not beyond that period. The Rebbe answers that in a leap year, the matzah would be used for thirteen months. Since the eiruv remains valid even then, it is clear that matzah can endure and remain usable for more than a full year.
Summary
The Rebbe rules that matzah from a previous year remains valid, as it retains its quality and edibility. The longstanding practice of using matzah for an eiruv chatzeros, even for over a year in a leap year, confirms that matzah can be relied upon beyond a full year.