Unleavened bread made from dough which is completely free of yeast or leavening and which is baked before the onset of fermentation. The opposite of matzah is ḥamets (regular leavened bread, cakes, etc.). Both are made of one of the five species of grain: wheat, rye, barley, oats, and spelt. The Halakhah determined that when any of these grains comes into contact with water, a process of fermentation begins 18 minutes later. Dough is made by kneading flour and water together; to qualify as matzah, it must be baked before fermentation can begin, i.e., before 18 minutes have elapsed.The Bible prohibits the consumption and possession of ḥamets for the seven days (eight outside Israel) of Passover and requires the consumption of at least an olive's weight (ka-zayit) of matzah on the Seder night (Ex. 12:15-20, 13:7; see also Pes. 28b, 120a). Matzah is associated with the sacrificial cult (Lev. 2:4-5), being the only type of dough permitted to be offered upon the altar as part of the meal offering.
Flour for matzah is generally ground from wheat, but any of the five species of grain may be used (Pes. 35a). The process of baking matzah begins with the guarding of the grain against any contact with water. Although the halakhah mandates such guarding from the time the grain is ground into flour, many strictly observant Jews will use only matzah where the grain has been guarded from the time of harvest. Such matzah is known as matzah shemurah ("guarded matzah") and is usually kneaded by hand, though machine-made matzah shemurah is also available. Many observant Jews, while not using matzah shemurah during all of Passover, eat it during the Seder. Water used in unleavened bread is called mayim she-lannu ("water that has rested overnight"). It is drawn from a well or river at dusk and left to "cool" until morning (Pes. 94b); the water is mixed with the guarded flour, after which the dough is kneaded, rolled flat, and pierced with a pin roller to prevent it from rising. It is then baked at a high temperature before 18 minutes have elapsed.
At the Seder, in addition to the normal blessing over bread, a special benediction is said before partaking of the unleavened bread: "Blessed are You, O Lord our God, Ruler of the universe, Who has sanctified us with Your commandments and commanded us to eat matzah." To dramatize the moment when unleavened bread is eaten at the Seder, the custom has arisen of refraining from eating matzah from Purim (approximately four weeks prior to Passover) or from the first of the month of Nisan (two weeks before Passover).
The symbolic association of matzah is twofold and dialectical. On the one hand, matzah is a symbol of freedom, based on Exodus 12:39: "They baked unleavened cakes of dough which they brought forth from Egypt, for it was not leavened; because they had been driven out of Egypt, and could not delay ..." The Passover Haggadah explains: "It is because there was not time for the dough of our ancestors to rise, before the Ruler of All revealed Himself and redeemed them." On the other hand, matzah is a symbol of the Egyptian slavery. Deuteronomy 16:3 refers to it as the bread of affliction (leḥem oni), and the Haggadah declares, "This is the bread of affliction that our ancestors ate in the Land of Egypt." Thus matzah recalls both slavery and redemption.
