In Shmot 12:17 we read “And you shall guard the matzot, for on this day I brought out your hosts from the land of Egypt. You must preserve this day for your generations, it is an eternal statute.”
In the Talmud, Psachim 38b we learn that to fulfil the mitzvah of eating matzah at the Seder, not only must the matzah be free of chametz (leaven), the matzah must be guarded from becoming chametz for the purpose of the mitzvah to eat matzah. This matzah is called Shmura as it was guarded.
According to the Shulchan Aruch 453:4, it is preferable for the grain to be guarded from the time of the reaping and onward.
Rashi explains “And you shall guard the matzot” so that they do not become chametz. From this the Sages said (Psachim 3:4): “If the dough has begun to rise, pat it with cold moisture”.
Rashi then quotes the Mechilta:
Rabbi Yoshiah said: Do not read the word as the matzot. Rather, read it as the mitzvot (commandments). In other words “And you shall guard the mitzvot” in order to teach us that just as one does not allow the matzah to become chametz, so too should one not allow a mitzvah to become chametz (delayed). Rather, if the opportunity to observe a mitzvah comes your way, perform it immediately.
Just as we are meticulous in preparing the matzot, paying attention to every small detail, so too should we give proper attention to our observance of every mitzvah.
Many people put an extra effort into getting ready for Pesach, even taking on extra stringencies, while they are more laid back about observing other mitzvot over the course of the year. Many rabbis and spiritual leaders say that the only time that they are asked Halachic questions is when it comes to preparing for Pesach.
The month of Nisan, when we take the mitzvot of Pesach very earnestly is a good time to focus on taking the year round mitzvot seriously as well. In this way, we can carry the holiness and spirituality of Pesach as well as our commitment to observing the entire Torah with us throughout the year.