Its is a mitzvah that the Passover matzot be made specifically for the purpose of fulfilling the obligation to eat matzot on Passover, as the verse (Exodus, 12:17) states: You shall guard the matzot. The matzah must be guarded to ensure that it does not become chametz; matzah which was not guarded may not be used on Passover.

How do we guard the matzah used on Passover? From the time that the wheat is taken to the mill to be ground into flour, it is kept under careful supervision to make sure that it does not come into contact with water or other moisture. We check it to ensure that the wheat is clean and whole.

The grinding, packing, and transporting of the wheat from the mill to the bakery is done under close supervision, to ensure that the ground wheat does not come into contact with water, and all of the utensils used for processing the wheat must be clean and dry. The wheat is not baked on the same day on which it was ground, for it is still warm from the processing and would therefore ferment and become chametz more rapidly.

It is watched while it is being kneaded to ensure that this is not done near an oven or open window which is exposed to the sun, lest the dough become hot and ferment quickly. The water which is used to make the dough is also specially prepared and guarded. All the utensils and machinery used for preparing the matzos starting from the sifters used on the flour must be clean and smoothed every hour so that no crumbs from a previous batch of dough are mixed with a new batch.

There are numerous other precautions which are to be observed while kneading and preparing the dough, and also regarding placing it into the oven to bake. The sole purpose of these measures is to fulfill the mitzvah of matzah. Since ordinary matzah is guarded, in the manner which we have described, from the time that the wheat is ground, in what way does it differ from the matzah which we refer to as shmurah, guarded.